2171631 has 48 divisors (see below), whose sum is σ = 3939840. Its totient is φ = 1048320.

The previous prime is 2171627. The next prime is 2171633. The reversal of 2171631 is 1361712.

2171631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2171631 - 2² = 2171627 is a prime.

It is a super-2 number, since 2×2171631² = 9431962400322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 2171598 and 2171607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2171633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 27450 + ... + 27528.

It is an arithmetic number, because the mean of its divisors is an integer number (82080).

2^2171631 is an apocalyptic number.

2171631 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

2171631 is a deficient number, since it is larger than the sum of its proper divisors (1768209).

2171631 is a wasteful number, since it uses less digits than its factorization.

2171631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 117 counting only the distinct ones).

The product of its digits is 252, while the sum is 21.

The square root of 2171631 is about 1473.6454797542. The cubic root of 2171631 is about 129.4976868347.

The spelling of 2171631 in words is "two million, one hundred seventy-one thousand, six hundred thirty-one".