21735940 has 24 divisors (see below), whose sum is σ = 46291392. Its totient is φ = 8571360.

The previous prime is 21735937. The next prime is 21736003. The reversal of 21735940 is 4953712.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a zygodrome in base 3.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6234 + ... + 9073.

It is an arithmetic number, because the mean of its divisors is an integer number (1928808).

Almost surely, 2^21735940 is an apocalyptic number.

21735940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21735940 is an abundant number, since it is smaller than the sum of its proper divisors (24555452).

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

21735940 is a wasteful number, since it uses less digits than its factorization.

21735940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15387 (or 15385 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 21735940 is about 4662.1818926335. The cubic root of 21735940 is about 279.0783471512.

The spelling of 21735940 in words is "twenty-one million, seven hundred thirty-five thousand, nine hundred forty".