161582737 has 4 divisors (see below), whose sum is σ = 165949876. Its totient is φ = 157215600.

The previous prime is 161582719. The next prime is 161582767. The reversal of 161582737 is 737285161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 737285161 = 131 ⋅5628131.

It can be written as a sum of positive squares in 2 ways, for example, as 102738496 + 58844241 = 10136^2 + 7671^2 .

It is a cyclic number.

It is not a de Polignac number, because 161582737 - 2⁷ = 161582609 is a prime.

It is a super-2 number, since 2×161582737² = 52217961792822338, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161582737.

It is not an unprimeable number, because it can be changed into a prime (161582767) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2183514 + ... + 2183587.

It is an arithmetic number, because the mean of its divisors is an integer number (41487469).

Almost surely, 2^161582737 is an apocalyptic number.

It is an amenable number.

161582737 is a deficient number, since it is larger than the sum of its proper divisors (4367139).

161582737 is an equidigital number, since it uses as much as digits as its factorization.

161582737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4367138.

The product of its digits is 70560, while the sum is 40.

The square root of 161582737 is about 12711.5198540536. The cubic root of 161582737 is about 544.6677401321.

The spelling of 161582737 in words is "one hundred sixty-one million, five hundred eighty-two thousand, seven hundred thirty-seven".