21261922 has 16 divisors (see below), whose sum is σ = 35186400. Its totient is φ = 9555040.

The previous prime is 21261887. The next prime is 21261941. The reversal of 21261922 is 22916212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3472 + ... + 7387.

It is an arithmetic number, because the mean of its divisors is an integer number (2199150).

Almost surely, 2^21261922 is an apocalyptic number.

21261922 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21261922 is a deficient number, since it is larger than the sum of its proper divisors (13924478).

21261922 is a wasteful number, since it uses less digits than its factorization.

21261922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10961.

The product of its digits is 864, while the sum is 25.

The square root of 21261922 is about 4611.0651697845. The cubic root of 21261922 is about 277.0347022170.

The spelling of 21261922 in words is "twenty-one million, two hundred sixty-one thousand, nine hundred twenty-two".