161605566661654 has 8 divisors (see below), whose sum is σ = 243859896998928. Its totient is φ = 80318934328680.

The previous prime is 161605566661631. The next prime is 161605566661661. The reversal of 161605566661654 is 456166665506161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×161605566661654² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 241924500657 + ... + 241924501324.

It is an arithmetic number, because the mean of its divisors is an integer number (30482487124866).

Almost surely, 2^{161605566661654} is an apocalyptic number.

161605566661654 is a deficient number, since it is larger than the sum of its proper divisors (82254330337274).

161605566661654 is a wasteful number, since it uses less digits than its factorization.

161605566661654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 483849002150.

The product of its (nonzero) digits is 139968000, while the sum is 64.

The spelling of 161605566661654 in words is "one hundred sixty-one trillion, six hundred five billion, five hundred sixty-six million, six hundred sixty-one thousand, six hundred fifty-four".