77938665 has 48 divisors (see below), whose sum is σ = 152723520. Its totient is φ = 33747840.

The previous prime is 77938639. The next prime is 77938667. The reversal of 77938665 is 56683977.

It is not a de Polignac number, because 77938665 - 2⁵ = 77938633 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77938667) 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, 11175 + ... + 16755.

It is an arithmetic number, because the mean of its divisors is an integer number (3181740).

Almost surely, 2^77938665 is an apocalyptic number.

It is an amenable number.

77938665 is a deficient number, since it is larger than the sum of its proper divisors (74784855).

77938665 is a wasteful number, since it uses less digits than its factorization.

77938665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5622 (or 5615 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 51.

The square root of 77938665 is about 8828.2877728357. The cubic root of 77938665 is about 427.1538458445.

The spelling of 77938665 in words is "seventy-seven million, nine hundred thirty-eight thousand, six hundred sixty-five".