221534404134781 has 2 divisors, whose sum is σ = 221534404134782. Its totient is φ = 221534404134780.

The previous prime is 221534404134737. The next prime is 221534404134833. The reversal of 221534404134781 is 187431404435122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220140753053881 + 1393651080900 = 14837141^2 + 1180530^2 .

It is a cyclic number.

It is not a de Polignac number, because 221534404134781 - 2⁷ = 221534404134653 is a prime.

It is a super-2 number, since 2×221534404134781² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221534404134881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110767202067390 + 110767202067391.

It is an arithmetic number, because the mean of its divisors is an integer number (110767202067391).

Almost surely, 2^{221534404134781} is an apocalyptic number.

It is an amenable number.

221534404134781 is a deficient number, since it is larger than the sum of its proper divisors (1).

221534404134781 is an equidigital number, since it uses as much as digits as its factorization.

221534404134781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2580480, while the sum is 49.

The spelling of 221534404134781 in words is "two hundred twenty-one trillion, five hundred thirty-four billion, four hundred four million, one hundred thirty-four thousand, seven hundred eighty-one".