20621240441 has 2 divisors, whose sum is σ = 20621240442. Its totient is φ = 20621240440.

The previous prime is 20621240413. The next prime is 20621240447. The reversal of 20621240441 is 14404212602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15732434041 + 4888806400 = 125429^2 + 69920^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20621240441 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20621240441.

It is not a weakly prime, because it can be changed into another prime (20621240447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10310620220 + 10310620221.

It is an arithmetic number, because the mean of its divisors is an integer number (10310620221).

Almost surely, 2^20621240441 is an apocalyptic number.

It is an amenable number.

20621240441 is a deficient number, since it is larger than the sum of its proper divisors (1).

20621240441 is an equidigital number, since it uses as much as digits as its factorization.

20621240441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3072, while the sum is 26.

The spelling of 20621240441 in words is "twenty billion, six hundred twenty-one million, two hundred forty thousand, four hundred forty-one".