1631689418 has 8 divisors (see below), whose sum is σ = 2513683812. Its totient is φ = 793794816.

The previous prime is 1631689399. The next prime is 1631689469. The reversal of 1631689418 is 8149861361.

It can be written as a sum of positive squares in 2 ways, for example, as 1206381289 + 425308129 = 34733^2 + 20623^2 .

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

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 3 ways as a sum of consecutive naturals, for example, 11024855 + ... + 11025002.

Almost surely, 2^1631689418 is an apocalyptic number.

1631689418 is a deficient number, since it is larger than the sum of its proper divisors (881994394).

1631689418 is a wasteful number, since it uses less digits than its factorization.

1631689418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22049896.

The product of its digits is 248832, while the sum is 47.

The square root of 1631689418 is about 40394.1755454917. The cubic root of 1631689418 is about 1177.2783722272.

The spelling of 1631689418 in words is "one billion, six hundred thirty-one million, six hundred eighty-nine thousand, four hundred eighteen".