721156461408 has 216 divisors, whose sum is σ = 2166721430328. Its totient is φ = 227490038784.

The previous prime is 721156461341. The next prime is 721156461461. The reversal of 721156461408 is 804164651127.

721156461408 is a `hidden beast` number, since 7 + 21 + 1 + 5 + 6 + 4 + 614 + 0 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 114049735 + ... + 114056057.

It is an arithmetic number, because the mean of its divisors is an integer number (10031117733).

Almost surely, 2^721156461408 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 721156461408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1083360715164).

721156461408 is an abundant number, since it is smaller than the sum of its proper divisors (1445564968920).

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

721156461408 is a wasteful number, since it uses less digits than its factorization.

721156461408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7474 (or 7444 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The spelling of 721156461408 in words is "seven hundred twenty-one billion, one hundred fifty-six million, four hundred sixty-one thousand, four hundred eight".