21532939 has 8 divisors (see below), whose sum is σ = 22154832. Its totient is φ = 20919840.

The previous prime is 21532937. The next prime is 21532943. The reversal of 21532939 is 93923512.

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

It is a cyclic number.

It is not a de Polignac number, because 21532939 - 2¹ = 21532937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21532937) 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, 2937 + ... + 7189.

It is an arithmetic number, because the mean of its divisors is an integer number (2769354).

Almost surely, 2^21532939 is an apocalyptic number.

21532939 is a deficient number, since it is larger than the sum of its proper divisors (621893).

21532939 is an equidigital number, since it uses as much as digits as its factorization.

21532939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4397.

The product of its digits is 14580, while the sum is 34.

The square root of 21532939 is about 4640.3597920851. The cubic root of 21532939 is about 278.2068186502.

The spelling of 21532939 in words is "twenty-one million, five hundred thirty-two thousand, nine hundred thirty-nine".