21292273 has 8 divisors (see below), whose sum is σ = 22638528. Its totient is φ = 19981104.

The previous prime is 21292253. The next prime is 21292277. The reversal of 21292273 is 37229212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21292273 - 2⁵ = 21292241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21292277) 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, 7515 + ... + 9952.

It is an arithmetic number, because the mean of its divisors is an integer number (2829816).

Almost surely, 2^21292273 is an apocalyptic number.

21292273 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21292273 is a deficient number, since it is larger than the sum of its proper divisors (1346255).

21292273 is a wasteful number, since it uses less digits than its factorization.

21292273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17543.

The product of its digits is 3024, while the sum is 28.

The square root of 21292273 is about 4614.3551012032. The cubic root of 21292273 is about 277.1664601790.

The spelling of 21292273 in words is "twenty-one million, two hundred ninety-two thousand, two hundred seventy-three".