21354680 has 32 divisors (see below), whose sum is σ = 48384000. Its totient is φ = 8482176.

The previous prime is 21354667. The next prime is 21354721. The reversal of 21354680 is 8645312.

It is a congruent number.

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, 4169 + ... + 7751.

It is an arithmetic number, because the mean of its divisors is an integer number (1512000).

Almost surely, 2^21354680 is an apocalyptic number.

21354680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21354680 is an abundant number, since it is smaller than the sum of its proper divisors (27029320).

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

21354680 is a wasteful number, since it uses less digits than its factorization.

21354680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3743 (or 3739 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 21354680 is about 4621.1124201863. The cubic root of 21354680 is about 277.4369848528.

Adding to 21354680 its reverse (8645312), we get a palindrome (29999992).

The spelling of 21354680 in words is "twenty-one million, three hundred fifty-four thousand, six hundred eighty".