21413511 has 32 divisors (see below), whose sum is σ = 36564480. Its totient is φ = 12132288.

The previous prime is 21413479. The next prime is 21413531. The reversal of 21413511 is 11531412.

It is not a de Polignac number, because 21413511 - 2⁵ = 21413479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413531) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25480 + ... + 26306.

It is an arithmetic number, because the mean of its divisors is an integer number (1142640).

Almost surely, 2^21413511 is an apocalyptic number.

21413511 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21413511 is a deficient number, since it is larger than the sum of its proper divisors (15150969).

21413511 is a wasteful number, since it uses less digits than its factorization.

21413511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980 (or 974 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 21413511 is about 4627.4735007345. The cubic root of 21413511 is about 277.6915259262.

Adding to 21413511 its reverse (11531412), we get a palindrome (32944923).

The spelling of 21413511 in words is "twenty-one million, four hundred thirteen thousand, five hundred eleven".