20215263566361 has 4 divisors (see below), whose sum is σ = 26953684755152. Its totient is φ = 13476842377572.

The previous prime is 20215263566347. The next prime is 20215263566369. The reversal of 20215263566361 is 16366536251202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20215263566361 - 2²² = 20215259372057 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20215263566361.

It is not an unprimeable number, because it can be changed into a prime (20215263566369) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3369210594391 + ... + 3369210594396.

It is an arithmetic number, because the mean of its divisors is an integer number (6738421188788).

Almost surely, 2^{20215263566361} is an apocalyptic number.

It is an amenable number.

20215263566361 is a deficient number, since it is larger than the sum of its proper divisors (6738421188791).

20215263566361 is an equidigital number, since it uses as much as digits as its factorization.

20215263566361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6738421188790.

The product of its (nonzero) digits is 2332800, while the sum is 48.

The spelling of 20215263566361 in words is "twenty trillion, two hundred fifteen billion, two hundred sixty-three million, five hundred sixty-six thousand, three hundred sixty-one".