21652743901 has 2 divisors, whose sum is σ = 21652743902. Its totient is φ = 21652743900.

The previous prime is 21652743887. The next prime is 21652743907. The reversal of 21652743901 is 10934725612.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20128231876 + 1524512025 = 141874^2 + 39045^2 .

It is a cyclic number.

It is not a de Polignac number, because 21652743901 - 2⁹ = 21652743389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21652743907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10826371950 + 10826371951.

It is an arithmetic number, because the mean of its divisors is an integer number (10826371951).

Almost surely, 2^21652743901 is an apocalyptic number.

It is an amenable number.

21652743901 is a deficient number, since it is larger than the sum of its proper divisors (1).

21652743901 is an equidigital number, since it uses as much as digits as its factorization.

21652743901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 40.

The spelling of 21652743901 in words is "twenty-one billion, six hundred fifty-two million, seven hundred forty-three thousand, nine hundred one".