21942529 has 16 divisors (see below), whose sum is σ = 27710208. Its totient is φ = 16929792.

The previous prime is 21942521. The next prime is 21942533. The reversal of 21942529 is 92524912.

It is a cyclic number.

It is not a de Polignac number, because 21942529 - 2³ = 21942521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21942494 and 21942503.

It is not an unprimeable number, because it can be changed into a prime (21942521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1272 + ... + 6745.

It is an arithmetic number, because the mean of its divisors is an integer number (1731888).

Almost surely, 2^21942529 is an apocalyptic number.

It is an amenable number.

21942529 is a deficient number, since it is larger than the sum of its proper divisors (5767679).

21942529 is a wasteful number, since it uses less digits than its factorization.

21942529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8064.

The product of its digits is 12960, while the sum is 34.

The square root of 21942529 is about 4684.2853243585. The cubic root of 21942529 is about 279.9597263504.

The spelling of 21942529 in words is "twenty-one million, nine hundred forty-two thousand, five hundred twenty-nine".