21653804707 has 2 divisors, whose sum is σ = 21653804708. Its totient is φ = 21653804706.

The previous prime is 21653804617. The next prime is 21653804743. The reversal of 21653804707 is 70740835612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21653804707 - 2¹⁹ = 21653280419 is a prime.

It is not a weakly prime, because it can be changed into another prime (21653801707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10826902353 + 10826902354.

It is an arithmetic number, because the mean of its divisors is an integer number (10826902354).

Almost surely, 2^21653804707 is an apocalyptic number.

21653804707 is a deficient number, since it is larger than the sum of its proper divisors (1).

21653804707 is an equidigital number, since it uses as much as digits as its factorization.

21653804707 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 43.

The spelling of 21653804707 in words is "twenty-one billion, six hundred fifty-three million, eight hundred four thousand, seven hundred seven".