77698690 has 16 divisors (see below), whose sum is σ = 143269560. Its totient is φ = 30321280.

The previous prime is 77698603. The next prime is 77698697. The reversal of 77698690 is 9689677.

77698690 = 733² + 734² + ... + 855².

It can be written as a sum of positive squares in 4 ways, for example, as 19527561 + 58171129 = 4419^2 + 7627^2 .

It is a super-2 number, since 2×77698690² = 12074172855432200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77698697) 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, 94345 + ... + 95164.

Almost surely, 2^77698690 is an apocalyptic number.

77698690 is a deficient number, since it is larger than the sum of its proper divisors (65570870).

77698690 is a wasteful number, since it uses less digits than its factorization.

77698690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189557.

The product of its (nonzero) digits is 1143072, while the sum is 52.

The square root of 77698690 is about 8814.6860409206. The cubic root of 77698690 is about 426.7149895085.

The spelling of 77698690 in words is "seventy-seven million, six hundred ninety-eight thousand, six hundred ninety".