21950215 has 16 divisors (see below), whose sum is σ = 30673728. Its totient is φ = 14766336.

The previous prime is 21950209. The next prime is 21950221. The reversal of 21950215 is 51205912.

It is an interprime number because it is at equal distance from previous prime (21950209) and next prime (21950221).

It is a cyclic number.

It is not a de Polignac number, because 21950215 - 2²³ = 13561607 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21950215.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4062 + ... + 7771.

It is an arithmetic number, because the mean of its divisors is an integer number (1917108).

Almost surely, 2^21950215 is an apocalyptic number.

21950215 is a deficient number, since it is larger than the sum of its proper divisors (8723513).

21950215 is a wasteful number, since it uses less digits than its factorization.

21950215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11898.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 21950215 is about 4685.1056551587. The cubic root of 21950215 is about 279.9924105086.

The spelling of 21950215 in words is "twenty-one million, nine hundred fifty thousand, two hundred fifteen".