721336351 has 4 divisors (see below), whose sum is σ = 721717704. Its totient is φ = 720955000.

The previous prime is 721336331. The next prime is 721336379. The reversal of 721336351 is 153633127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 153633127 = 769 ⋅199783.

It is a cyclic number.

It is not a de Polignac number, because 721336351 - 2²³ = 712947743 is a prime.

It is a super-2 number, since 2×721336351² = 1040652262547990402, 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 (721336321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 187825 + ... + 191626.

It is an arithmetic number, because the mean of its divisors is an integer number (180429426).

Almost surely, 2^721336351 is an apocalyptic number.

721336351 is a deficient number, since it is larger than the sum of its proper divisors (381353).

721336351 is a wasteful number, since it uses less digits than its factorization.

721336351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381352.

The product of its digits is 11340, while the sum is 31.

The square root of 721336351 is about 26857.7056168244. The cubic root of 721336351 is about 896.8351186093.

Adding to 721336351 its reverse (153633127), we get a palindrome (874969478).

The spelling of 721336351 in words is "seven hundred twenty-one million, three hundred thirty-six thousand, three hundred fifty-one".