721497051 has 160 divisors (see below), whose sum is σ = 1379980800. Its totient is φ = 369515520.

The previous prime is 721497011. The next prime is 721497059. The reversal of 721497051 is 150794127.

It is a happy number.

721497051 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 721497051 - 2²³ = 713108443 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 721496997 and 721497015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721497059) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 6619185 + ... + 6619293.

It is an arithmetic number, because the mean of its divisors is an integer number (8624880).

Almost surely, 2^721497051 is an apocalyptic number.

721497051 is a deficient number, since it is larger than the sum of its proper divisors (658483749).

721497051 is a wasteful number, since it uses less digits than its factorization.

721497051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 36.

The square root of 721497051 is about 26860.6971428517. The cubic root of 721497051 is about 896.9017129251.

The spelling of 721497051 in words is "seven hundred twenty-one million, four hundred ninety-seven thousand, fifty-one".