7781452438 has 4 divisors (see below), whose sum is σ = 11672178660. Its totient is φ = 3890726218.

The previous prime is 7781452429. The next prime is 7781452439. The reversal of 7781452438 is 8342541877.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×7781452438² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 7781452391 and 7781452400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7781452439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1945363108 + ... + 1945363111.

It is an arithmetic number, because the mean of its divisors is an integer number (2918044665).

Almost surely, 2^7781452438 is an apocalyptic number.

7781452438 is a deficient number, since it is larger than the sum of its proper divisors (3890726222).

7781452438 is a wasteful number, since it uses less digits than its factorization.

7781452438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3890726221.

The product of its digits is 1505280, while the sum is 49.

The square root of 7781452438 is about 88212.5412739028. The cubic root of 7781452438 is about 1981.6192955118.

The spelling of 7781452438 in words is "seven billion, seven hundred eighty-one million, four hundred fifty-two thousand, four hundred thirty-eight".