631552081 has 8 divisors (see below), whose sum is σ = 643907880. Its totient is φ = 619212672.

The previous prime is 631552049. The next prime is 631552087. The reversal of 631552081 is 180255136.

It can be written as a sum of positive squares in 4 ways, for example, as 273737025 + 357815056 = 16545^2 + 18916^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 631552081 - 2⁵ = 631552049 is a prime.

It is a super-2 number, since 2×631552081² = 797716062030861122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631552087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98275 + ... + 104503.

It is an arithmetic number, because the mean of its divisors is an integer number (80488485).

Almost surely, 2^631552081 is an apocalyptic number.

It is an amenable number.

631552081 is a deficient number, since it is larger than the sum of its proper divisors (12355799).

631552081 is a wasteful number, since it uses less digits than its factorization.

631552081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8195.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 631552081 is about 25130.6999703550. The cubic root of 631552081 is about 857.9653002595.

The spelling of 631552081 in words is "six hundred thirty-one million, five hundred fifty-two thousand, eighty-one".