21892129 has 8 divisors (see below), whose sum is σ = 25882560. Its totient is φ = 18117456.

The previous prime is 21892109. The next prime is 21892139. The reversal of 21892129 is 92129812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21892129 - 2⁵ = 21892097 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21892094 and 21892103.

It is not an unprimeable number, because it can be changed into a prime (21892109) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53719 + ... + 54124.

It is an arithmetic number, because the mean of its divisors is an integer number (3235320).

Almost surely, 2^21892129 is an apocalyptic number.

21892129 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21892129 is a deficient number, since it is larger than the sum of its proper divisors (3990431).

21892129 is a wasteful number, since it uses less digits than its factorization.

21892129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107879.

The product of its digits is 5184, while the sum is 34.

The square root of 21892129 is about 4678.9025422635. The cubic root of 21892129 is about 279.7452146576.

The spelling of 21892129 in words is "twenty-one million, eight hundred ninety-two thousand, one hundred twenty-nine".