721893607540 has 24 divisors (see below), whose sum is σ = 1732544658432. Its totient is φ = 247506379680.

The previous prime is 721893607537. The next prime is 721893607559. The reversal of 721893607540 is 45706398127.

It is a super-2 number, since 2×721893607540² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

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, 2578191316 + ... + 2578191595.

It is an arithmetic number, because the mean of its divisors is an integer number (72189360768).

It is a 1-persistent number, because it is pandigital, but 2⋅721893607540 = 1443787215080 is not.

Almost surely, 2^721893607540 is an apocalyptic number.

721893607540 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

721893607540 is an abundant number, since it is smaller than the sum of its proper divisors (1010651050892).

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

721893607540 is a wasteful number, since it uses less digits than its factorization.

721893607540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5156382927 (or 5156382925 counting only the distinct ones).

The product of its (nonzero) digits is 2540160, while the sum is 52.

The spelling of 721893607540 in words is "seven hundred twenty-one billion, eight hundred ninety-three million, six hundred seven thousand, five hundred forty".