21051036 has 24 divisors (see below), whose sum is σ = 54577040. Its totient is φ = 7016976.

The previous prime is 21051029. The next prime is 21051047. The reversal of 21051036 is 63015012.

It is a super-2 number, since 2×21051036² = 886292233346592, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

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, 97351 + ... + 97566.

Almost surely, 2^21051036 is an apocalyptic number.

It is an amenable number.

21051036 is an abundant number, since it is smaller than the sum of its proper divisors (33526004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21051036 is a wasteful number, since it uses less digits than its factorization.

21051036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194930 (or 194922 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 21051036 is about 4588.1407999319. The cubic root of 21051036 is about 276.1157359603.

Adding to 21051036 its reverse (63015012), we get a palindrome (84066048).

The spelling of 21051036 in words is "twenty-one million, fifty-one thousand, thirty-six".