721430157 has 16 divisors (see below), whose sum is σ = 1103299712. Its totient is φ = 410754240.

The previous prime is 721430153. The next prime is 721430159. The reversal of 721430157 is 751034127.

It is not a de Polignac number, because 721430157 - 2² = 721430153 is a prime.

It is a super-2 number, since 2×721430157² = 1040922942858089298, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721430153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56194 + ... + 67827.

It is an arithmetic number, because the mean of its divisors is an integer number (68956232).

Almost surely, 2^721430157 is an apocalyptic number.

It is an amenable number.

721430157 is a deficient number, since it is larger than the sum of its proper divisors (381869555).

721430157 is a wasteful number, since it uses less digits than its factorization.

721430157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124308.

The product of its (nonzero) digits is 5880, while the sum is 30.

The square root of 721430157 is about 26859.4519117572. The cubic root of 721430157 is about 896.8739931549.

The spelling of 721430157 in words is "seven hundred twenty-one million, four hundred thirty thousand, one hundred fifty-seven".