161451810 has 48 divisors (see below), whose sum is σ = 452068344. Its totient is φ = 39741696.

The previous prime is 161451803. The next prime is 161451817. The reversal of 161451810 is 18154161.

It is an interprime number because it is at equal distance from previous prime (161451803) and next prime (161451817).

It can be written as a sum of positive squares in 4 ways, for example, as 44876601 + 116575209 = 6699^2 + 10797^2 .

It is a super-2 number, since 2×161451810² = 52133373904552200, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161451817) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67827 + ... + 70166.

Almost surely, 2^161451810 is an apocalyptic number.

161451810 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161451810 is an abundant number, since it is smaller than the sum of its proper divisors (290616534).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161451810 is a wasteful number, since it uses less digits than its factorization.

161451810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138019 (or 138016 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 27.

The square root of 161451810 is about 12706.3688754892. The cubic root of 161451810 is about 544.5205895474.

It can be divided in two parts, 161451 and 810, that added together give a palindrome (162261).

The spelling of 161451810 in words is "one hundred sixty-one million, four hundred fifty-one thousand, eight hundred ten".