721751133064531 has 8 divisors (see below), whose sum is σ = 723218404688640. Its totient is φ = 720283989928392.

The previous prime is 721751133064499. The next prime is 721751133064547. The reversal of 721751133064531 is 135460331157127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 721751133064531 - 2⁵ = 721751133064499 is a prime.

It is a super-2 number, since 2×721751133064531² (a number of 31 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (721751133061531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20872041 + ... + 43349098.

It is an arithmetic number, because the mean of its divisors is an integer number (90402300586080).

Almost surely, 2^{721751133064531} is an apocalyptic number.

721751133064531 is a deficient number, since it is larger than the sum of its proper divisors (1467271624109).

721751133064531 is a wasteful number, since it uses less digits than its factorization.

721751133064531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64243985.

The product of its (nonzero) digits is 1587600, while the sum is 49.

The spelling of 721751133064531 in words is "seven hundred twenty-one trillion, seven hundred fifty-one billion, one hundred thirty-three million, sixty-four thousand, five hundred thirty-one".