731561431 has 2 divisors, whose sum is σ = 731561432. Its totient is φ = 731561430.

The previous prime is 731561429. The next prime is 731561443. The reversal of 731561431 is 134165137.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 731561431 - 2¹ = 731561429 is a prime.

It is a super-2 number, since 2×731561431² = 1070364254653535522, which contains 22 as substring.

Together with 731561429, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 731561393 and 731561402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (731562431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 365780715 + 365780716.

It is an arithmetic number, because the mean of its divisors is an integer number (365780716).

Almost surely, 2^731561431 is an apocalyptic number.

731561431 is a deficient number, since it is larger than the sum of its proper divisors (1).

731561431 is an equidigital number, since it uses as much as digits as its factorization.

731561431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7560, while the sum is 31.

The square root of 731561431 is about 27047.3923142324. The cubic root of 731561431 is about 901.0528546810.

The spelling of 731561431 in words is "seven hundred thirty-one million, five hundred sixty-one thousand, four hundred thirty-one".