21901366 has 16 divisors (see below), whose sum is σ = 33359040. Its totient is φ = 10783240.

The previous prime is 21901291. The next prime is 21901381. The reversal of 21901366 is 66310912.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46665 + ... + 47131.

It is an arithmetic number, because the mean of its divisors is an integer number (2084940).

Almost surely, 2^21901366 is an apocalyptic number.

21901366 is a deficient number, since it is larger than the sum of its proper divisors (11457674).

21901366 is a wasteful number, since it uses less digits than its factorization.

21901366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 779.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 21901366 is about 4679.8895286107. The cubic root of 21901366 is about 279.7845536548.

The spelling of 21901366 in words is "twenty-one million, nine hundred one thousand, three hundred sixty-six".