21950979 has 8 divisors (see below), whose sum is σ = 29309952. Its totient is φ = 14613000.

The previous prime is 21950977. The next prime is 21950983. The reversal of 21950979 is 97905912.

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

It is not a de Polignac number, because 21950979 - 2¹ = 21950977 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21950979.

It is not an unprimeable number, because it can be changed into a prime (21950977) 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, 2619 + ... + 7124.

It is an arithmetic number, because the mean of its divisors is an integer number (3663744).

Almost surely, 2^21950979 is an apocalyptic number.

21950979 is a deficient number, since it is larger than the sum of its proper divisors (7358973).

21950979 is an equidigital number, since it uses as much as digits as its factorization.

21950979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10497.

The product of its (nonzero) digits is 51030, while the sum is 42.

The square root of 21950979 is about 4685.1871894301. The cubic root of 21950979 is about 279.9956589463.

The spelling of 21950979 in words is "twenty-one million, nine hundred fifty thousand, nine hundred seventy-nine".