21756950 has 12 divisors (see below), whose sum is σ = 40468020. Its totient is φ = 8702760.

The previous prime is 21756949. The next prime is 21756971. The reversal of 21756950 is 5965712.

It is a self number, because there is not a number n which added to its sum of digits gives 21756950.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 217520 + ... + 217619.

It is an arithmetic number, because the mean of its divisors is an integer number (3372335).

Almost surely, 2^21756950 is an apocalyptic number.

21756950 is a deficient number, since it is larger than the sum of its proper divisors (18711070).

21756950 is a wasteful number, since it uses less digits than its factorization.

21756950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 435151 (or 435146 counting only the distinct ones).

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 21756950 is about 4664.4345852418. The cubic root of 21756950 is about 279.1682374110.

The spelling of 21756950 in words is "twenty-one million, seven hundred fifty-six thousand, nine hundred fifty".