631006220881 has 9 divisors (see below), whose sum is σ = 670321991899. Its totient is φ = 593875498144.

The previous prime is 631006220869. The next prime is 631006220939. The reversal of 631006220881 is 188022600136.

It is a happy number.

The square root of 631006220881 is 794359.

It is a perfect power (a square), and thus also a powerful number.

631006220881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 491267819025 + 139738401856 = 700905^2 + 373816^2 .

It is not a de Polignac number, because 631006220881 - 2⁷ = 631006220753 is a prime.

It is a super-2 number, since 2×631006220881² (a number of 24 digits) contains 22 as substring.

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 631006220881.

It is not an unprimeable number, because it can be changed into a prime (631006220681) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 13480740 + ... + 13527466.

Almost surely, 2^631006220881 is an apocalyptic number.

631006220881 is the 794359-th square number.

631006220881 is the 397180-th centered octagonal number.

It is an amenable number.

631006220881 is a deficient number, since it is larger than the sum of its proper divisors (39315771018).

631006220881 is an frugal number, since it uses more digits than its factorization.

631006220881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93488 (or 46744 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 37.

The spelling of 631006220881 in words is "six hundred thirty-one billion, six million, two hundred twenty thousand, eight hundred eighty-one".