21246631 has 8 divisors (see below), whose sum is σ = 24310944. Its totient is φ = 18189600.

The previous prime is 21246629. The next prime is 21246637. The reversal of 21246631 is 13664212.

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

It is a cyclic number.

It is not a de Polignac number, because 21246631 - 2¹ = 21246629 is a prime.

It is a super-2 number, since 2×21246631² = 902838657700322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21246596 and 21246605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21246637) 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 7 ways as a sum of consecutive naturals, for example, 7941 + ... + 10273.

It is an arithmetic number, because the mean of its divisors is an integer number (3038868).

Almost surely, 2^21246631 is an apocalyptic number.

21246631 is a deficient number, since it is larger than the sum of its proper divisors (3064313).

21246631 is a wasteful number, since it uses less digits than its factorization.

21246631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3641.

The product of its digits is 1728, while the sum is 25.

The square root of 21246631 is about 4609.4067948056. The cubic root of 21246631 is about 276.9682743318.

The spelling of 21246631 in words is "twenty-one million, two hundred forty-six thousand, six hundred thirty-one".