661932031 has 2 divisors, whose sum is σ = 661932032. Its totient is φ = 661932030.

The previous prime is 661931993. The next prime is 661932097. The reversal of 661932031 is 130239166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661932031 - 2¹³ = 661923839 is a prime.

It is a super-2 number, since 2×661932031² = 876308027327569922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 661931984 and 661932002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (662932031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330966015 + 330966016.

It is an arithmetic number, because the mean of its divisors is an integer number (330966016).

Almost surely, 2^661932031 is an apocalyptic number.

661932031 is a deficient number, since it is larger than the sum of its proper divisors (1).

661932031 is an equidigital number, since it uses as much as digits as its factorization.

661932031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 661932031 is about 25728.0397815302. The cubic root of 661932031 is about 871.5075070010.

The spelling of 661932031 in words is "six hundred sixty-one million, nine hundred thirty-two thousand, thirty-one".