161956429 has 4 divisors (see below), whose sum is σ = 163560060. Its totient is φ = 160352800.

The previous prime is 161956427. The next prime is 161956453. The reversal of 161956429 is 924659161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 924659161 = 67 ⋅13800883.

It can be written as a sum of positive squares in 2 ways, for example, as 75429225 + 86527204 = 8685^2 + 9302^2 .

It is a cyclic number.

It is not a de Polignac number, because 161956429 - 2¹ = 161956427 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161956423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 801664 + ... + 801865.

It is an arithmetic number, because the mean of its divisors is an integer number (40890015).

Almost surely, 2^161956429 is an apocalyptic number.

It is an amenable number.

161956429 is a deficient number, since it is larger than the sum of its proper divisors (1603631).

161956429 is a wasteful number, since it uses less digits than its factorization.

161956429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1603630.

The product of its digits is 116640, while the sum is 43.

The square root of 161956429 is about 12726.2103157224. The cubic root of 161956429 is about 545.0873007752.

The spelling of 161956429 in words is "one hundred sixty-one million, nine hundred fifty-six thousand, four hundred twenty-nine".