21960961 has 8 divisors (see below), whose sum is σ = 24120000. Its totient is φ = 19829040.

The previous prime is 21960947. The next prime is 21960977. The reversal of 21960961 is 16906912.

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

It is not a de Polignac number, because 21960961 - 2⁷ = 21960833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21960931) 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, 5061 + ... + 8338.

It is an arithmetic number, because the mean of its divisors is an integer number (3015000).

Almost surely, 2^21960961 is an apocalyptic number.

It is an amenable number.

21960961 is a deficient number, since it is larger than the sum of its proper divisors (2159039).

21960961 is a wasteful number, since it uses less digits than its factorization.

21960961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13559.

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 21960961 is about 4686.2523406236. The cubic root of 21960961 is about 280.0380943068.

The spelling of 21960961 in words is "twenty-one million, nine hundred sixty thousand, nine hundred sixty-one".