21493465 has 16 divisors (see below), whose sum is σ = 31029120. Its totient is φ = 13962240.

The previous prime is 21493453. The next prime is 21493481. The reversal of 21493465 is 56439412.

It is a happy number.

It is not a de Polignac number, because 21493465 - 2⁹ = 21492953 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21493465.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15496 + ... + 16825.

It is an arithmetic number, because the mean of its divisors is an integer number (1939320).

Almost surely, 2^21493465 is an apocalyptic number.

It is an amenable number.

21493465 is a deficient number, since it is larger than the sum of its proper divisors (9535655).

21493465 is a wasteful number, since it uses less digits than its factorization.

21493465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32352.

The product of its digits is 25920, while the sum is 34.

The square root of 21493465 is about 4636.1045070188. The cubic root of 21493465 is about 278.0367125402.

The spelling of 21493465 in words is "twenty-one million, four hundred ninety-three thousand, four hundred sixty-five".