660697779 has 32 divisors (see below), whose sum is σ = 1019543040. Its totient is φ = 372782592.

The previous prime is 660697757. The next prime is 660697783. The reversal of 660697779 is 977796066.

It is not a de Polignac number, because 660697779 - 2⁷ = 660697651 is a prime.

It is not an unprimeable number, because it can be changed into a prime (660697799) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1207584 + ... + 1208130.

It is an arithmetic number, because the mean of its divisors is an integer number (31860720).

Almost surely, 2^660697779 is an apocalyptic number.

660697779 is a deficient number, since it is larger than the sum of its proper divisors (358845261).

660697779 is a wasteful number, since it uses less digits than its factorization.

660697779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1179.

The product of its (nonzero) digits is 6001128, while the sum is 57.

The square root of 660697779 is about 25704.0420751290. The cubic root of 660697779 is about 870.9654930719.

The spelling of 660697779 in words is "six hundred sixty million, six hundred ninety-seven thousand, seven hundred seventy-nine".