21621092 has 12 divisors (see below), whose sum is σ = 38091900. Its totient is φ = 10737696.

The previous prime is 21621091. The next prime is 21621097. The reversal of 21621092 is 29012612.

It can be written as a sum of positive squares in 2 ways, for example, as 9897316 + 11723776 = 3146^2 + 3424^2 .

It is not an unprimeable number, because it can be changed into a prime (21621091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17543 + ... + 18734.

It is an arithmetic number, because the mean of its divisors is an integer number (3174325).

Almost surely, 2^21621092 is an apocalyptic number.

It is an amenable number.

21621092 is a deficient number, since it is larger than the sum of its proper divisors (16470808).

21621092 is a wasteful number, since it uses less digits than its factorization.

21621092 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36430 (or 36428 counting only the distinct ones).

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

The square root of 21621092 is about 4649.8485996858. The cubic root of 21621092 is about 278.5859490380.

The spelling of 21621092 in words is "twenty-one million, six hundred twenty-one thousand, ninety-two".