77921472 has 56 divisors (see below), whose sum is σ = 218303856. Its totient is φ = 24444928.

The previous prime is 77921471. The next prime is 77921483. The reversal of 77921472 is 27412977.

It is a self number, because there is not a number n which added to its sum of digits gives 77921472.

It is not an unprimeable number, because it can be changed into a prime (77921471) 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, 8673 + ... + 15200.

Almost surely, 2^77921472 is an apocalyptic number.

It is an amenable number.

77921472 is an abundant number, since it is smaller than the sum of its proper divisors (140382384).

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

77921472 is a wasteful number, since it uses less digits than its factorization.

77921472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23905 (or 23895 counting only the distinct ones).

The product of its digits is 49392, while the sum is 39.

The square root of 77921472 is about 8827.3139742506. The cubic root of 77921472 is about 427.1224339808.

The spelling of 77921472 in words is "seventy-seven million, nine hundred twenty-one thousand, four hundred seventy-two".