161366774399 has 16 divisors (see below), whose sum is σ = 174280619520. Its totient is φ = 148950019680.

The previous prime is 161366774357. The next prime is 161366774411. The reversal of 161366774399 is 993477663161.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161366774399 is a prime.

It is a super-2 number, since 2×161366774399² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161366774339) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1225334 + ... + 1350620.

It is an arithmetic number, because the mean of its divisors is an integer number (10892538720).

Almost surely, 2^161366774399 is an apocalyptic number.

161366774399 is a deficient number, since it is larger than the sum of its proper divisors (12913845121).

161366774399 is a wasteful number, since it uses less digits than its factorization.

161366774399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127270.

The product of its digits is 30862944, while the sum is 62.

The spelling of 161366774399 in words is "one hundred sixty-one billion, three hundred sixty-six million, seven hundred seventy-four thousand, three hundred ninety-nine".