21290092709 has 2 divisors, whose sum is σ = 21290092710. Its totient is φ = 21290092708.

The previous prime is 21290092661. The next prime is 21290092717. The reversal of 21290092709 is 90729009212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17280417025 + 4009675684 = 131455^2 + 63322^2 .

It is a cyclic number.

It is not a de Polignac number, because 21290092709 - 2²⁴ = 21273315493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21290092609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10645046354 + 10645046355.

It is an arithmetic number, because the mean of its divisors is an integer number (10645046355).

Almost surely, 2^21290092709 is an apocalyptic number.

It is an amenable number.

21290092709 is a deficient number, since it is larger than the sum of its proper divisors (1).

21290092709 is an equidigital number, since it uses as much as digits as its factorization.

21290092709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 41.

The spelling of 21290092709 in words is "twenty-one billion, two hundred ninety million, ninety-two thousand, seven hundred nine".