7645421520 has 240 divisors, whose sum is σ = 29048265792. Its totient is φ = 1853383680.

The previous prime is 7645421477. The next prime is 7645421527. The reversal of 7645421520 is 251245467.

It is a happy number.

7645421520 is a `hidden beast` number, since 7 + 64 + 54 + 21 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×7645421520² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7645421527) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 195964 + ... + 231716.

Almost surely, 2^7645421520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7645421520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14524132896).

7645421520 is an abundant number, since it is smaller than the sum of its proper divisors (21402844272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7645421520 is a wasteful number, since it uses less digits than its factorization.

7645421520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35792 (or 35774 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The square root of 7645421520 is about 87438.1010772764. The cubic root of 7645421520 is about 1970.0041674094.

Adding to 7645421520 its reverse (251245467), we get a palindrome (7896666987).

The spelling of 7645421520 in words is "seven billion, six hundred forty-five million, four hundred twenty-one thousand, five hundred twenty".