21949953 has 8 divisors (see below), whose sum is σ = 30210816. Its totient is φ = 14161200.

The previous prime is 21949951. The next prime is 21949969. The reversal of 21949953 is 35994912.

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

It is not a de Polignac number, because 21949953 - 2¹ = 21949951 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21949951) 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, 117918 + ... + 118103.

It is an arithmetic number, because the mean of its divisors is an integer number (3776352).

Almost surely, 2^21949953 is an apocalyptic number.

It is an amenable number.

21949953 is a deficient number, since it is larger than the sum of its proper divisors (8260863).

21949953 is a wasteful number, since it uses less digits than its factorization.

21949953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236055.

The product of its digits is 87480, while the sum is 42.

The square root of 21949953 is about 4685.0776941263. The cubic root of 21949953 is about 279.9912964982.

The spelling of 21949953 in words is "twenty-one million, nine hundred forty-nine thousand, nine hundred fifty-three".