21966967 has 8 divisors (see below), whose sum is σ = 24012432. Its totient is φ = 19929600.

The previous prime is 21966961. The next prime is 21967019. The reversal of 21966967 is 76966912.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21966967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21966961) 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, 4617 + ... + 8077.

It is an arithmetic number, because the mean of its divisors is an integer number (3001554).

Almost surely, 2^21966967 is an apocalyptic number.

21966967 is a deficient number, since it is larger than the sum of its proper divisors (2045465).

21966967 is a wasteful number, since it uses less digits than its factorization.

21966967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4049.

The product of its digits is 244944, while the sum is 46.

The square root of 21966967 is about 4686.8931073793. The cubic root of 21966967 is about 280.0636207473.

Subtracting 21966967 from its reverse (76966912), we obtain a palindrome (54999945).

The spelling of 21966967 in words is "twenty-one million, nine hundred sixty-six thousand, nine hundred sixty-seven".