21877131206401 has 2 divisors, whose sum is σ = 21877131206402. Its totient is φ = 21877131206400.

The previous prime is 21877131206317. The next prime is 21877131206453. The reversal of 21877131206401 is 10460213177812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20155789830400 + 1721341376001 = 4489520^2 + 1311999^2 .

It is a cyclic number.

It is not a de Polignac number, because 21877131206401 - 2¹¹ = 21877131204353 is a prime.

It is not a weakly prime, because it can be changed into another prime (21877131206471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10938565603200 + 10938565603201.

It is an arithmetic number, because the mean of its divisors is an integer number (10938565603201).

Almost surely, 2^{21877131206401} is an apocalyptic number.

It is an amenable number.

21877131206401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21877131206401 is an equidigital number, since it uses as much as digits as its factorization.

21877131206401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112896, while the sum is 43.

The spelling of 21877131206401 in words is "twenty-one trillion, eight hundred seventy-seven billion, one hundred thirty-one million, two hundred six thousand, four hundred one".