21901344 has 24 divisors (see below), whose sum is σ = 57491280. Its totient is φ = 7300416.

The previous prime is 21901291. The next prime is 21901381. The reversal of 21901344 is 44310912.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113974 + ... + 114165.

It is an arithmetic number, because the mean of its divisors is an integer number (2395470).

Almost surely, 2^21901344 is an apocalyptic number.

21901344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21901344 is an abundant number, since it is smaller than the sum of its proper divisors (35589936).

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

21901344 is a wasteful number, since it uses less digits than its factorization.

21901344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228152 (or 228144 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21901344 is about 4679.8871781273. The cubic root of 21901344 is about 279.7844599733.

The spelling of 21901344 in words is "twenty-one million, nine hundred one thousand, three hundred forty-four".