731399864 has 64 divisors (see below), whose sum is σ = 1542240000. Its totient is φ = 322882560.

The previous prime is 731399827. The next prime is 731399869. The reversal of 731399864 is 468993137.

It is a super-2 number, since 2×731399864² = 1069891522118436992, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (731399869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 285662 + ... + 288210.

It is an arithmetic number, because the mean of its divisors is an integer number (24097500).

Almost surely, 2^731399864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 731399864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (771120000).

731399864 is an abundant number, since it is smaller than the sum of its proper divisors (810840136).

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

731399864 is a wasteful number, since it uses less digits than its factorization.

731399864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2688 (or 2684 counting only the distinct ones).

The product of its digits is 979776, while the sum is 50.

The square root of 731399864 is about 27044.4054103617. The cubic root of 731399864 is about 900.9865166088.

The spelling of 731399864 in words is "seven hundred thirty-one million, three hundred ninety-nine thousand, eight hundred sixty-four".