21149535 has 32 divisors (see below), whose sum is σ = 38527488. Its totient is φ = 9806720.

The previous prime is 21149509. The next prime is 21149539. The reversal of 21149535 is 53594112.

It is not a de Polignac number, because 21149535 - 2⁷ = 21149407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21149539) 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, 1009 + ... + 6581.

It is an arithmetic number, because the mean of its divisors is an integer number (1203984).

Almost surely, 2^21149535 is an apocalyptic number.

21149535 is a deficient number, since it is larger than the sum of its proper divisors (17377953).

21149535 is a wasteful number, since it uses less digits than its factorization.

21149535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5615.

The product of its digits is 5400, while the sum is 30.

The square root of 21149535 is about 4598.8623593232. The cubic root of 21149535 is about 276.5457197837.

The spelling of 21149535 in words is "twenty-one million, one hundred forty-nine thousand, five hundred thirty-five".