21427364 has 24 divisors (see below), whose sum is σ = 45111360. Its totient is φ = 8699616.

The previous prime is 21427349. The next prime is 21427369. The reversal of 21427364 is 46372412.

It is not an unprimeable number, because it can be changed into a prime (21427369) 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, 19607 + ... + 20670.

It is an arithmetic number, because the mean of its divisors is an integer number (1879640).

Almost surely, 2^21427364 is an apocalyptic number.

It is an amenable number.

21427364 is an abundant number, since it is smaller than the sum of its proper divisors (23683996).

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

21427364 is a wasteful number, since it uses less digits than its factorization.

21427364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40307 (or 40305 counting only the distinct ones).

The product of its digits is 8064, while the sum is 29.

The square root of 21427364 is about 4628.9700798342. The cubic root of 21427364 is about 277.7513951595.

Adding to 21427364 its reverse (46372412), we get a palindrome (67799776).

The spelling of 21427364 in words is "twenty-one million, four hundred twenty-seven thousand, three hundred sixty-four".