21427996 has 24 divisors (see below), whose sum is σ = 39584160. Its totient is φ = 10129152.

The previous prime is 21427961. The next prime is 21427997. The reversal of 21427996 is 69972412.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21427997) 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, 6880 + ... + 9496.

It is an arithmetic number, because the mean of its divisors is an integer number (1649340).

Almost surely, 2^21427996 is an apocalyptic number.

It is an amenable number.

21427996 is a deficient number, since it is larger than the sum of its proper divisors (18156164).

21427996 is a wasteful number, since it uses less digits than its factorization.

21427996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2733 (or 2731 counting only the distinct ones).

The product of its digits is 54432, while the sum is 40.

The square root of 21427996 is about 4629.0383450561. The cubic root of 21427996 is about 277.7541258914.

The spelling of 21427996 in words is "twenty-one million, four hundred twenty-seven thousand, nine hundred ninety-six".