21802453 has 2 divisors, whose sum is σ = 21802454. Its totient is φ = 21802452.

The previous prime is 21802439. The next prime is 21802457. The reversal of 21802453 is 35420812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21362884 + 439569 = 4622^2 + 663^2 .

It is a cyclic number.

It is not a de Polignac number, because 21802453 - 2¹³ = 21794261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21802457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10901226 + 10901227.

It is an arithmetic number, because the mean of its divisors is an integer number (10901227).

Almost surely, 2^21802453 is an apocalyptic number.

It is an amenable number.

21802453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21802453 is an equidigital number, since it uses as much as digits as its factorization.

21802453 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 21802453 is about 4669.3096920209. The cubic root of 21802453 is about 279.3627215767.

The spelling of 21802453 in words is "twenty-one million, eight hundred two thousand, four hundred fifty-three".