1640712771 has 24 divisors (see below), whose sum is σ = 2392157040. Its totient is φ = 1083580416.

The previous prime is 1640712767. The next prime is 1640712779. The reversal of 1640712771 is 1772170461.

1640712771 is a `hidden beast` number, since 1 + 640 + 7 + 1 + 2 + 7 + 7 + 1 = 666.

It is not a de Polignac number, because 1640712771 - 2² = 1640712767 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1640712779) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 720691 + ... + 722963.

It is an arithmetic number, because the mean of its divisors is an integer number (99673210).

Almost surely, 2^1640712771 is an apocalyptic number.

1640712771 is a deficient number, since it is larger than the sum of its proper divisors (751444269).

1640712771 is a wasteful number, since it uses less digits than its factorization.

1640712771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2995 (or 2992 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 36.

The square root of 1640712771 is about 40505.7128193049. The cubic root of 1640712771 is about 1179.4445271723. Note that the first 3 decimals are identical.

The spelling of 1640712771 in words is "one billion, six hundred forty million, seven hundred twelve thousand, seven hundred seventy-one".