21485131 has 8 divisors (see below), whose sum is σ = 21833280. Its totient is φ = 21139272.

The previous prime is 21485129. The next prime is 21485147. The reversal of 21485131 is 13158412.

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 21485131 - 2¹ = 21485129 is a prime.

It is a super-2 number, since 2×21485131² = 923221708174322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21485096 and 21485105.

It is not an unprimeable number, because it can be changed into a prime (21485111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31116 + ... + 31798.

It is an arithmetic number, because the mean of its divisors is an integer number (2729160).

Almost surely, 2^21485131 is an apocalyptic number.

21485131 is a deficient number, since it is larger than the sum of its proper divisors (348149).

21485131 is an equidigital number, since it uses as much as digits as its factorization.

21485131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1145.

The product of its digits is 960, while the sum is 25.

The square root of 21485131 is about 4635.2056049328. The cubic root of 21485131 is about 278.0007720421. Note that the first 3 decimals are identical.

The spelling of 21485131 in words is "twenty-one million, four hundred eighty-five thousand, one hundred thirty-one".