647992031 has 2 divisors, whose sum is σ = 647992032. Its totient is φ = 647992030.

The previous prime is 647992021. The next prime is 647992057. The reversal of 647992031 is 130299746.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647992031 is a prime.

It is a super-2 number, since 2×647992031² = 839787344479009922, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 647992031.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647992021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323996015 + 323996016.

It is an arithmetic number, because the mean of its divisors is an integer number (323996016).

Almost surely, 2^647992031 is an apocalyptic number.

647992031 is a deficient number, since it is larger than the sum of its proper divisors (1).

647992031 is an equidigital number, since it uses as much as digits as its factorization.

647992031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 41.

The square root of 647992031 is about 25455.6875962917. The cubic root of 647992031 is about 865.3461948592.

The spelling of 647992031 in words is "six hundred forty-seven million, nine hundred ninety-two thousand, thirty-one".