21952130 has 32 divisors (see below), whose sum is σ = 41601600. Its totient is φ = 8327872.

The previous prime is 21952129. The next prime is 21952141. The reversal of 21952130 is 3125912.

21952130 = 856² + 857² + ... + 884².

It is a junction number, because it is equal to n+sod(n) for n = 21952096 and 21952105.

It is an unprimeable number.

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, 16469 + ... + 17751.

It is an arithmetic number, because the mean of its divisors is an integer number (1300050).

Almost surely, 2^21952130 is an apocalyptic number.

21952130 is a deficient number, since it is larger than the sum of its proper divisors (19649470).

21952130 is a wasteful number, since it uses less digits than its factorization.

21952130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1378.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 21952130 is about 4685.3100217595. The cubic root of 21952130 is about 280.0005527200. Note that the first 3 decimals are identical.

The spelling of 21952130 in words is "twenty-one million, nine hundred fifty-two thousand, one hundred thirty".