161865425 has 12 divisors (see below), whose sum is σ = 200872560. Its totient is φ = 129389520.

The previous prime is 161865419. The next prime is 161865439. The reversal of 161865425 is 524568161.

It is a happy number.

It is not a de Polignac number, because 161865425 - 2²⁰ = 160816849 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 53606 + ... + 56544.

It is an arithmetic number, because the mean of its divisors is an integer number (16739380).

Almost surely, 2^161865425 is an apocalyptic number.

It is an amenable number.

161865425 is a deficient number, since it is larger than the sum of its proper divisors (39007135).

161865425 is a wasteful number, since it uses less digits than its factorization.

161865425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5152 (or 5147 counting only the distinct ones).

The product of its digits is 57600, while the sum is 38.

The square root of 161865425 is about 12722.6343577107. The cubic root of 161865425 is about 544.9851860295.

The spelling of 161865425 in words is "one hundred sixty-one million, eight hundred sixty-five thousand, four hundred twenty-five".