21096787 has 2 divisors, whose sum is σ = 21096788. Its totient is φ = 21096786.

The previous prime is 21096763. The next prime is 21096791. The reversal of 21096787 is 78769012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21096787 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (21096487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10548393 + 10548394.

It is an arithmetic number, because the mean of its divisors is an integer number (10548394).

Almost surely, 2^21096787 is an apocalyptic number.

21096787 is a deficient number, since it is larger than the sum of its proper divisors (1).

21096787 is an equidigital number, since it uses as much as digits as its factorization.

21096787 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 21096787 is about 4593.1238825009. The cubic root of 21096787 is about 276.3156220920.

The spelling of 21096787 in words is "twenty-one million, ninety-six thousand, seven hundred eighty-seven".