161458508761 has 9 divisors (see below), whose sum is σ = 177475781343. Its totient is φ = 146776444320.

The previous prime is 161458508737. The next prime is 161458508779. The reversal of 161458508761 is 167805854161.

The square root of 161458508761 is 401819.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 123292979161 + 38165529600 = 351131^2 + 195360^2 .

It is a de Polignac number, because none of the positive numbers 2^k-161458508761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161458508699 and 161458508708.

It is not an unprimeable number, because it can be changed into a prime (161458506761) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4401745 + ... + 4438273.

Almost surely, 2^161458508761 is an apocalyptic number.

161458508761 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

161458508761 is the 401819-th square number.

161458508761 is the 200910-th centered octagonal number.

It is an amenable number.

161458508761 is a deficient number, since it is larger than the sum of its proper divisors (16017272582).

161458508761 is an frugal number, since it uses more digits than its factorization.

161458508761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73080 (or 36540 counting only the distinct ones).

The product of its (nonzero) digits is 1612800, while the sum is 52.

The spelling of 161458508761 in words is "one hundred sixty-one billion, four hundred fifty-eight million, five hundred eight thousand, seven hundred sixty-one".