631221494 has 4 divisors (see below), whose sum is σ = 946832244. Its totient is φ = 315610746.

The previous prime is 631221491. The next prime is 631221529. The reversal of 631221494 is 494122136.

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

It is a self number, because there is not a number n which added to its sum of digits gives 631221494.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631221491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157805372 + ... + 157805375.

It is an arithmetic number, because the mean of its divisors is an integer number (236708061).

Almost surely, 2^631221494 is an apocalyptic number.

631221494 is a deficient number, since it is larger than the sum of its proper divisors (315610750).

631221494 is a wasteful number, since it uses less digits than its factorization.

631221494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315610749.

The product of its digits is 10368, while the sum is 32.

The square root of 631221494 is about 25124.1217557948. The cubic root of 631221494 is about 857.8155730046.

The spelling of 631221494 in words is "six hundred thirty-one million, two hundred twenty-one thousand, four hundred ninety-four".