731391940 has 24 divisors (see below), whose sum is σ = 1539303192. Its totient is φ = 291912960.

The previous prime is 731391937. The next prime is 731391953. The reversal of 731391940 is 49193137.

It can be written as a sum of positive squares in 4 ways, for example, as 30625156 + 700766784 = 5534^2 + 26472^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 731391940.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30871 + ... + 49150.

It is an arithmetic number, because the mean of its divisors is an integer number (64137633).

Almost surely, 2^731391940 is an apocalyptic number.

It is an amenable number.

731391940 is an abundant number, since it is smaller than the sum of its proper divisors (807911252).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

731391940 is a wasteful number, since it uses less digits than its factorization.

731391940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80487 (or 80485 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 731391940 is about 27044.2589101643. The cubic root of 731391940 is about 900.9832628287.

The spelling of 731391940 in words is "seven hundred thirty-one million, three hundred ninety-one thousand, nine hundred forty".