721614551 has 8 divisors (see below), whose sum is σ = 825102624. Its totient is φ = 618226560.

The previous prime is 721614499. The next prime is 721614611. The reversal of 721614551 is 155416127.

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

It is a de Polignac number, because none of the positive numbers 2^k-721614551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721614151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8870 + ... + 39011.

It is an arithmetic number, because the mean of its divisors is an integer number (103137828).

Almost surely, 2^721614551 is an apocalyptic number.

721614551 is a deficient number, since it is larger than the sum of its proper divisors (103488073).

721614551 is a wasteful number, since it uses less digits than its factorization.

721614551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50041.

The product of its digits is 8400, while the sum is 32.

The square root of 721614551 is about 26862.8842643526. The cubic root of 721614551 is about 896.9503988395.

The spelling of 721614551 in words is "seven hundred twenty-one million, six hundred fourteen thousand, five hundred fifty-one".