721468011621 has 16 divisors (see below), whose sum is σ = 1099416780800. Its totient is φ = 412253577648.

The previous prime is 721468011587. The next prime is 721468011623. The reversal of 721468011621 is 126110864127.

It is not a de Polignac number, because 721468011621 - 2⁹ = 721468011109 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 721468011621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721468011623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79620 + ... + 1203858.

It is an arithmetic number, because the mean of its divisors is an integer number (68713548800).

Almost surely, 2^721468011621 is an apocalyptic number.

It is an amenable number.

721468011621 is a deficient number, since it is larger than the sum of its proper divisors (377948769179).

721468011621 is a wasteful number, since it uses less digits than its factorization.

721468011621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1154808.

The product of its (nonzero) digits is 32256, while the sum is 39.

Adding to 721468011621 its reverse (126110864127), we get a palindrome (847578875748).

The spelling of 721468011621 in words is "seven hundred twenty-one billion, four hundred sixty-eight million, eleven thousand, six hundred twenty-one".