721755468722 has 18 divisors (see below), whose sum is σ = 1098226122237. Its totient is φ = 355752898200.

The previous prime is 721755468701. The next prime is 721755468739. The reversal of 721755468722 is 227864557127.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 627721859521 + 94033609201 = 792289^2 + 306649^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=600731.

It is a super-2 number, since 2×721755468722² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (56) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 85299572 + ... + 85308032.

Almost surely, 2^721755468722 is an apocalyptic number.

721755468722 is a deficient number, since it is larger than the sum of its proper divisors (376470653515).

721755468722 is an frugal number, since it uses more digits than its factorization.

721755468722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17066 (or 8534 counting only the distinct ones).

The product of its digits is 13171200, while the sum is 56.

The spelling of 721755468722 in words is "seven hundred twenty-one billion, seven hundred fifty-five million, four hundred sixty-eight thousand, seven hundred twenty-two".