161563025 has 12 divisors (see below), whose sum is σ = 215749212. Its totient is φ = 119307840.

The previous prime is 161563021. The next prime is 161563033. The reversal of 161563025 is 520365161.

It can be written as a sum of positive squares in 6 ways, for example, as 69422224 + 92140801 = 8332^2 + 9599^2 .

It is not a de Polignac number, because 161563025 - 2² = 161563021 is a prime.

It is a super-2 number, since 2×161563025² = 52205222094301250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161563021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 248234 + ... + 248883.

It is an arithmetic number, because the mean of its divisors is an integer number (17979101).

Almost surely, 2^161563025 is an apocalyptic number.

It is an amenable number.

161563025 is a deficient number, since it is larger than the sum of its proper divisors (54186187).

161563025 is a wasteful number, since it uses less digits than its factorization.

161563025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 497140 (or 497135 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 161563025 is about 12710.7444707224. The cubic root of 161563025 is about 544.6455906391.

The spelling of 161563025 in words is "one hundred sixty-one million, five hundred sixty-three thousand, twenty-five".