21901473 has 12 divisors (see below), whose sum is σ = 34511568. Its totient is φ = 13273560.

The previous prime is 21901463. The next prime is 21901489. The reversal of 21901473 is 37410912.

21901473 is a `hidden beast` number, since 2 + 190 + 1 + 473 = 666.

It is not a de Polignac number, because 21901473 - 2¹³ = 21893281 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21901403) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 110515 + ... + 110712.

It is an arithmetic number, because the mean of its divisors is an integer number (2875964).

Almost surely, 2^21901473 is an apocalyptic number.

It is an amenable number.

21901473 is a deficient number, since it is larger than the sum of its proper divisors (12610095).

21901473 is a wasteful number, since it uses less digits than its factorization.

21901473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221244 (or 221241 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21901473 is about 4679.9009604905. The cubic root of 21901473 is about 279.7850092870.

It can be divided in two parts, 2190 and 1473, that added together give a palindrome (3663).

The spelling of 21901473 in words is "twenty-one million, nine hundred one thousand, four hundred seventy-three".