221947123194157 has 2 divisors, whose sum is σ = 221947123194158. Its totient is φ = 221947123194156.

The previous prime is 221947123194119. The next prime is 221947123194197. The reversal of 221947123194157 is 751491321749122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 218326954843881 + 3620168350276 = 14775891^2 + 1902674^2 .

It is a cyclic number.

It is not a de Polignac number, because 221947123194157 - 2¹⁹ = 221947122669869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221947123194197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110973561597078 + 110973561597079.

It is an arithmetic number, because the mean of its divisors is an integer number (110973561597079).

Almost surely, 2^{221947123194157} is an apocalyptic number.

It is an amenable number.

221947123194157 is a deficient number, since it is larger than the sum of its proper divisors (1).

221947123194157 is an equidigital number, since it uses as much as digits as its factorization.

221947123194157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7620480, while the sum is 58.

The spelling of 221947123194157 in words is "two hundred twenty-one trillion, nine hundred forty-seven billion, one hundred twenty-three million, one hundred ninety-four thousand, one hundred fifty-seven".