21967404 has 12 divisors (see below), whose sum is σ = 51257304. Its totient is φ = 7322464.

The previous prime is 21967403. The next prime is 21967409. The reversal of 21967404 is 40476912.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a plaindrome in base 11.

It is a zygodrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (21967403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 915297 + ... + 915320.

It is an arithmetic number, because the mean of its divisors is an integer number (4271442).

Almost surely, 2^21967404 is an apocalyptic number.

It is an amenable number.

21967404 is an abundant number, since it is smaller than the sum of its proper divisors (29289900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21967404 is a wasteful number, since it uses less digits than its factorization.

21967404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1830624 (or 1830622 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 21967404 is about 4686.9397265167. The cubic root of 21967404 is about 280.0654778841.

The spelling of 21967404 in words is "twenty-one million, nine hundred sixty-seven thousand, four hundred four".