21696877 has 2 divisors, whose sum is σ = 21696878. Its totient is φ = 21696876.

The previous prime is 21696859. The next prime is 21696923. The reversal of 21696877 is 77869612.

It is a happy number.

It is an a-pointer prime, because the next prime (21696923) can be obtained adding 21696877 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20484676 + 1212201 = 4526^2 + 1101^2 .

It is a cyclic number.

It is not a de Polignac number, because 21696877 - 2¹⁵ = 21664109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21696277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10848438 + 10848439.

It is an arithmetic number, because the mean of its divisors is an integer number (10848439).

Almost surely, 2^21696877 is an apocalyptic number.

It is an amenable number.

21696877 is a deficient number, since it is larger than the sum of its proper divisors (1).

21696877 is an equidigital number, since it uses as much as digits as its factorization.

21696877 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 46.

The square root of 21696877 is about 4657.9906612186. The cubic root of 21696877 is about 278.9110639224.

The spelling of 21696877 in words is "twenty-one million, six hundred ninety-six thousand, eight hundred seventy-seven".