7638521081 has 8 divisors (see below), whose sum is σ = 7787383200. Its totient is φ = 7490305600.

The previous prime is 7638521047. The next prime is 7638521101. The reversal of 7638521081 is 1801258367.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7638521081 - 2⁶ = 7638521017 is a prime.

It is a super-2 number, since 2×7638521081² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7638520081) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137771 + ... + 185088.

It is an arithmetic number, because the mean of its divisors is an integer number (973422900).

Almost surely, 2^7638521081 is an apocalyptic number.

It is an amenable number.

7638521081 is a deficient number, since it is larger than the sum of its proper divisors (148862119).

7638521081 is a wasteful number, since it uses less digits than its factorization.

7638521081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323319.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 7638521081 is about 87398.6331758112. The cubic root of 7638521081 is about 1969.4113077760.

The spelling of 7638521081 in words is "seven billion, six hundred thirty-eight million, five hundred twenty-one thousand, eighty-one".