21547960501 has 2 divisors, whose sum is σ = 21547960502. Its totient is φ = 21547960500.

The previous prime is 21547960457. The next prime is 21547960549. The reversal of 21547960501 is 10506974512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15299216100 + 6248744401 = 123690^2 + 79049^2 .

It is a cyclic number.

It is not a de Polignac number, because 21547960501 - 2¹⁹ = 21547436213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21547960571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10773980250 + 10773980251.

It is an arithmetic number, because the mean of its divisors is an integer number (10773980251).

Almost surely, 2^21547960501 is an apocalyptic number.

It is an amenable number.

21547960501 is a deficient number, since it is larger than the sum of its proper divisors (1).

21547960501 is an equidigital number, since it uses as much as digits as its factorization.

21547960501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 75600, while the sum is 40.

The spelling of 21547960501 in words is "twenty-one billion, five hundred forty-seven million, nine hundred sixty thousand, five hundred one".