21602129 has 16 divisors (see below), whose sum is σ = 23587200. Its totient is φ = 19721856.

The previous prime is 21602099. The next prime is 21602137. The reversal of 21602129 is 92120612.

It is a de Polignac number, because none of the positive numbers 2^k-21602129 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21602149) 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 15 ways as a sum of consecutive naturals, for example, 92597 + ... + 92829.

It is an arithmetic number, because the mean of its divisors is an integer number (1474200).

Almost surely, 2^21602129 is an apocalyptic number.

21602129 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21602129 is a deficient number, since it is larger than the sum of its proper divisors (1985071).

21602129 is a wasteful number, since it uses less digits than its factorization.

21602129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 21602129 is about 4647.8090537370. The cubic root of 21602129 is about 278.5044796630.

The spelling of 21602129 in words is "twenty-one million, six hundred two thousand, one hundred twenty-nine".