21033297 has 8 divisors (see below), whose sum is σ = 31160480. Its totient is φ = 14022180.

The previous prime is 21033289. The next prime is 21033317. The reversal of 21033297 is 79233012.

It is not a de Polignac number, because 21033297 - 2³ = 21033289 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 779011 = 21033297 / (2 + 1 + 0 + 3 + 3 + 2 + 9 + 7).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21033297.

It is not an unprimeable number, because it can be changed into a prime (21033277) 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, 389479 + ... + 389532.

It is an arithmetic number, because the mean of its divisors is an integer number (3895060).

Almost surely, 2^21033297 is an apocalyptic number.

21033297 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21033297 is a deficient number, since it is larger than the sum of its proper divisors (10127183).

21033297 is an equidigital number, since it uses as much as digits as its factorization.

21033297 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 779020 (or 779014 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 27.

The square root of 21033297 is about 4586.2072565465. The cubic root of 21033297 is about 276.0381563504.

The spelling of 21033297 in words is "twenty-one million, thirty-three thousand, two hundred ninety-seven".