647211939 has 48 divisors (see below), whose sum is σ = 972410880. Its totient is φ = 382536000.

The previous prime is 647211923. The next prime is 647211979. The reversal of 647211939 is 939112746.

It is not a de Polignac number, because 647211939 - 2⁴ = 647211923 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 647211939.

It is not an unprimeable number, because it can be changed into a prime (647211979) 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, 4656132 + ... + 4656270.

It is an arithmetic number, because the mean of its divisors is an integer number (20258560).

Almost surely, 2^647211939 is an apocalyptic number.

647211939 is a deficient number, since it is larger than the sum of its proper divisors (325198941).

647211939 is a wasteful number, since it uses less digits than its factorization.

647211939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392 (or 381 counting only the distinct ones).

The product of its digits is 81648, while the sum is 42.

The square root of 647211939 is about 25440.3604337674. The cubic root of 647211939 is about 864.9988033886.

The spelling of 647211939 in words is "six hundred forty-seven million, two hundred eleven thousand, nine hundred thirty-nine".