721481907611 has 4 divisors (see below), whose sum is σ = 721538158800. Its totient is φ = 721425656424.

The previous prime is 721481907599. The next prime is 721481907637. The reversal of 721481907611 is 116709184127.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 721481907611 - 2¹⁴ = 721481891227 is a prime.

It is a super-2 number, since 2×721481907611² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (721481907691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28106351 + ... + 28132008.

It is an arithmetic number, because the mean of its divisors is an integer number (180384539700).

Almost surely, 2^721481907611 is an apocalyptic number.

721481907611 is a deficient number, since it is larger than the sum of its proper divisors (56251189).

721481907611 is a wasteful number, since it uses less digits than its factorization.

721481907611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56251188.

The product of its (nonzero) digits is 169344, while the sum is 47.

The spelling of 721481907611 in words is "seven hundred twenty-one billion, four hundred eighty-one million, nine hundred seven thousand, six hundred eleven".