21102402 has 16 divisors (see below), whose sum is σ = 42783840. Its totient is φ = 6937632.

The previous prime is 21102391. The next prime is 21102409. The reversal of 21102402 is 20420112.

It is a super-2 number, since 2×21102402² = 890622740339208, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21102409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23652 + ... + 24527.

It is an arithmetic number, because the mean of its divisors is an integer number (2673990).

Almost surely, 2^21102402 is an apocalyptic number.

21102402 is an abundant number, since it is smaller than the sum of its proper divisors (21681438).

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

21102402 is a wasteful number, since it uses less digits than its factorization.

21102402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48257.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21102402 is about 4593.7350816084. The cubic root of 21102402 is about 276.3401341119.

Adding to 21102402 its reverse (20420112), we get a palindrome (41522514).

The spelling of 21102402 in words is "twenty-one million, one hundred two thousand, four hundred two".