1631688 has 16 divisors (see below), whose sum is σ = 4079280. Its totient is φ = 543888.

The previous prime is 1631683. The next prime is 1631723. The reversal of 1631688 is 8861361.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1631683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33970 + ... + 34017.

It is an arithmetic number, because the mean of its divisors is an integer number (254955).

2^1631688 is an apocalyptic number.

It is an amenable number.

1631688 is an abundant number, since it is smaller than the sum of its proper divisors (2447592).

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

1631688 is a wasteful number, since it uses less digits than its factorization.

1631688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67996 (or 67992 counting only the distinct ones).

The product of its digits is 6912, while the sum is 33.

The square root of 1631688 is about 1277.3754342401. The cubic root of 1631688 is about 117.7278031194.

Adding to 1631688 its sum of digits (33), we get a triangular number (1631721 = T₁₈₀₆).

The spelling of 1631688 in words is "one million, six hundred thirty-one thousand, six hundred eighty-eight".