21227363761 has 2 divisors, whose sum is σ = 21227363762. Its totient is φ = 21227363760.

The previous prime is 21227363747. The next prime is 21227363767. The reversal of 21227363761 is 16736372212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21222953761 + 4410000 = 145681^2 + 2100^2 .

It is a cyclic number.

It is not a de Polignac number, because 21227363761 - 2⁹ = 21227363249 is a prime.

It is not a weakly prime, because it can be changed into another prime (21227363767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10613681880 + 10613681881.

It is an arithmetic number, because the mean of its divisors is an integer number (10613681881).

Almost surely, 2^21227363761 is an apocalyptic number.

It is an amenable number.

21227363761 is a deficient number, since it is larger than the sum of its proper divisors (1).

21227363761 is an equidigital number, since it uses as much as digits as its factorization.

21227363761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 40.

The spelling of 21227363761 in words is "twenty-one billion, two hundred twenty-seven million, three hundred sixty-three thousand, seven hundred sixty-one".