21427036 has 12 divisors (see below), whose sum is σ = 37539880. Its totient is φ = 10701360.

The previous prime is 21427013. The next prime is 21427037. The reversal of 21427036 is 63072412.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21427036.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21427037) 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, 1771 + ... + 6781.

Almost surely, 2^21427036 is an apocalyptic number.

It is an amenable number.

21427036 is a deficient number, since it is larger than the sum of its proper divisors (16112844).

21427036 is a wasteful number, since it uses less digits than its factorization.

21427036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6084 (or 6082 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 21427036 is about 4628.9346506513. The cubic root of 21427036 is about 277.7499779231.

Adding to 21427036 its reverse (63072412), we get a palindrome (84499448).

The spelling of 21427036 in words is "twenty-one million, four hundred twenty-seven thousand, thirty-six".