631313820 has 36 divisors (see below), whose sum is σ = 1914985800. Its totient is φ = 168350304.

The previous prime is 631313807. The next prime is 631313843. The reversal of 631313820 is 28313136.

It is a happy number.

631313820 is a `hidden beast` number, since 631 + 3 + 1 + 3 + 8 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 1753470 + ... + 1753829.

It is an arithmetic number, because the mean of its divisors is an integer number (53194050).

Almost surely, 2^631313820 is an apocalyptic number.

631313820 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

631313820 is an abundant number, since it is smaller than the sum of its proper divisors (1283671980).

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

631313820 is a wasteful number, since it uses less digits than its factorization.

631313820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3507314 (or 3507309 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 631313820 is about 25125.9590861722. The cubic root of 631313820 is about 857.8573939397.

Adding to 631313820 its reverse (28313136), we get a palindrome (659626956).

The spelling of 631313820 in words is "six hundred thirty-one million, three hundred thirteen thousand, eight hundred twenty".