161658157754 has 4 divisors (see below), whose sum is σ = 242487236634. Its totient is φ = 80829078876.

The previous prime is 161658157753. The next prime is 161658157781. The reversal of 161658157754 is 457751856161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 457751856161 = 17093 ⋅26780077.

It can be written as a sum of positive squares in only one way, i.e., 112243090729 + 49415067025 = 335027^2 + 222295^2 .

It is a super-2 number, since 2×161658157754² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161658157754.

It is not an unprimeable number, because it can be changed into a prime (161658157753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40414539437 + ... + 40414539440.

Almost surely, 2^161658157754 is an apocalyptic number.

161658157754 is a deficient number, since it is larger than the sum of its proper divisors (80829078880).

161658157754 is an equidigital number, since it uses as much as digits as its factorization.

161658157754 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80829078879.

The product of its digits is 7056000, while the sum is 56.

The spelling of 161658157754 in words is "one hundred sixty-one billion, six hundred fifty-eight million, one hundred fifty-seven thousand, seven hundred fifty-four".