81774707928 has 16 divisors (see below), whose sum is σ = 204436769880. Its totient is φ = 27258235968.

The previous prime is 81774707921. The next prime is 81774707951. The reversal of 81774707928 is 82970747718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81774707921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1703639725 + ... + 1703639772.

Almost surely, 2^81774707928 is an apocalyptic number.

It is an amenable number.

81774707928 is an abundant number, since it is smaller than the sum of its proper divisors (122662061952).

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

81774707928 is a wasteful number, since it uses less digits than its factorization.

81774707928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3407279506 (or 3407279502 counting only the distinct ones).

The product of its (nonzero) digits is 11063808, while the sum is 60.

The spelling of 81774707928 in words is "eighty-one billion, seven hundred seventy-four million, seven hundred seven thousand, nine hundred twenty-eight".