21492495 has 24 divisors (see below), whose sum is σ = 37623456. Its totient is φ = 11348928.

The previous prime is 21492479. The next prime is 21492533. The reversal of 21492495 is 59429412.

It is a Cunningham number, because it is equal to 4636²-1.

It is not a de Polignac number, because 21492495 - 2⁴ = 21492479 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2317 + ... + 6953.

It is an arithmetic number, because the mean of its divisors is an integer number (1567644).

Almost surely, 2^21492495 is an apocalyptic number.

21492495 is a deficient number, since it is larger than the sum of its proper divisors (16130961).

21492495 is a wasteful number, since it uses less digits than its factorization.

21492495 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4751 (or 4748 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 21492495 is about 4635.9998921484. Note that the first 3 decimals coincide. The cubic root of 21492495 is about 278.0325298787.

The spelling of 21492495 in words is "twenty-one million, four hundred ninety-two thousand, four hundred ninety-five".