21876553 has 2 divisors, whose sum is σ = 21876554. Its totient is φ = 21876552.

The previous prime is 21876539. The next prime is 21876587. The reversal of 21876553 is 35567812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12616704 + 9259849 = 3552^2 + 3043^2 .

It is a cyclic number.

It is not a de Polignac number, because 21876553 - 2⁵ = 21876521 is a prime.

It is not a weakly prime, because it can be changed into another prime (21876593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10938276 + 10938277.

It is an arithmetic number, because the mean of its divisors is an integer number (10938277).

Almost surely, 2^21876553 is an apocalyptic number.

It is an amenable number.

21876553 is a deficient number, since it is larger than the sum of its proper divisors (1).

21876553 is an equidigital number, since it uses as much as digits as its factorization.

21876553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50400, while the sum is 37.

The square root of 21876553 is about 4677.2377532043. The cubic root of 21876553 is about 279.6788537406.

The spelling of 21876553 in words is "twenty-one million, eight hundred seventy-six thousand, five hundred fifty-three".