630551881 has 4 divisors (see below), whose sum is σ = 639189652. Its totient is φ = 621914112.

The previous prime is 630551861. The next prime is 630551897. The reversal of 630551881 is 188155036.

630551881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 365383225 + 265168656 = 19115^2 + 16284^2 .

It is a cyclic number.

It is not a de Polignac number, because 630551881 - 2¹¹ = 630549833 is a prime.

It is a super-2 number, since 2×630551881² = 795191349265276322, which 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 630551881.

It is not an unprimeable number, because it can be changed into a prime (630551861) 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, 4318776 + ... + 4318921.

It is an arithmetic number, because the mean of its divisors is an integer number (159797413).

Almost surely, 2^630551881 is an apocalyptic number.

It is an amenable number.

630551881 is a deficient number, since it is larger than the sum of its proper divisors (8637771).

630551881 is an equidigital number, since it uses as much as digits as its factorization.

630551881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8637770.

The product of its (nonzero) digits is 28800, while the sum is 37.

The square root of 630551881 is about 25110.7921221136. The cubic root of 630551881 is about 857.5121360980.

The spelling of 630551881 in words is "six hundred thirty million, five hundred fifty-one thousand, eight hundred eighty-one".