20963921 has 8 divisors (see below), whose sum is σ = 23183904. Its totient is φ = 18796320.

The previous prime is 20963909. The next prime is 20963923. The reversal of 20963921 is 12936902.

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

It is a cyclic number.

It is not a de Polignac number, because 20963921 - 2¹⁰ = 20962897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20963923) 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, 12251 + ... + 13856.

It is an arithmetic number, because the mean of its divisors is an integer number (2897988).

Almost surely, 2^20963921 is an apocalyptic number.

It is an amenable number.

20963921 is a deficient number, since it is larger than the sum of its proper divisors (2219983).

20963921 is a wasteful number, since it uses less digits than its factorization.

20963921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26191.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 20963921 is about 4578.6374610794. The cubic root of 20963921 is about 275.7343282981.

The spelling of 20963921 in words is "twenty million, nine hundred sixty-three thousand, nine hundred twenty-one".