631987220 has 24 divisors (see below), whose sum is σ = 1342089000. Its totient is φ = 249953792.

The previous prime is 631987217. The next prime is 631987241. The reversal of 631987220 is 22789136.

It can be written as a sum of positive squares in 4 ways, for example, as 142515844 + 489471376 = 11938^2 + 22124^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 175745 + ... + 179304.

It is an arithmetic number, because the mean of its divisors is an integer number (55920375).

Almost surely, 2^631987220 is an apocalyptic number.

It is an amenable number.

631987220 is an abundant number, since it is smaller than the sum of its proper divisors (710101780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

631987220 is a wasteful number, since it uses less digits than its factorization.

631987220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355147 (or 355145 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 631987220 is about 25139.3559981158. The cubic root of 631987220 is about 858.1623008788.

It can be divided in two parts, 6319 and 87220, that added together give a palindrome (93539).

The spelling of 631987220 in words is "six hundred thirty-one million, nine hundred eighty-seven thousand, two hundred twenty".