21237323 has 2 divisors, whose sum is σ = 21237324. Its totient is φ = 21237322.

The previous prime is 21237319. The next prime is 21237331. The reversal of 21237323 is 32373212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21237323 - 2² = 21237319 is a prime.

It is not a weakly prime, because it can be changed into another prime (21237343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10618661 + 10618662.

It is an arithmetic number, because the mean of its divisors is an integer number (10618662).

Almost surely, 2^21237323 is an apocalyptic number.

21237323 is a deficient number, since it is larger than the sum of its proper divisors (1).

21237323 is an equidigital number, since it uses as much as digits as its factorization.

21237323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 23.

The square root of 21237323 is about 4608.3970098072. The cubic root of 21237323 is about 276.9278224713.

The spelling of 21237323 in words is "twenty-one million, two hundred thirty-seven thousand, three hundred twenty-three".