221173126157 has 2 divisors, whose sum is σ = 221173126158. Its totient is φ = 221173126156.

The previous prime is 221173126121. The next prime is 221173126193. The reversal of 221173126157 is 751621371122.

It is a balanced prime because it is at equal distance from previous prime (221173126121) and next prime (221173126193).

It can be written as a sum of positive squares in only one way, i.e., 199432803241 + 21740322916 = 446579^2 + 147446^2 .

It is a cyclic number.

It is not a de Polignac number, because 221173126157 - 2²⁸ = 220904690701 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221173126157.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221173128157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110586563078 + 110586563079.

It is an arithmetic number, because the mean of its divisors is an integer number (110586563079).

Almost surely, 2^221173126157 is an apocalyptic number.

It is an amenable number.

221173126157 is a deficient number, since it is larger than the sum of its proper divisors (1).

221173126157 is an equidigital number, since it uses as much as digits as its factorization.

221173126157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 35280, while the sum is 38.

Adding to 221173126157 its reverse (751621371122), we get a palindrome (972794497279).

The spelling of 221173126157 in words is "two hundred twenty-one billion, one hundred seventy-three million, one hundred twenty-six thousand, one hundred fifty-seven".