161847820 has 24 divisors (see below), whose sum is σ = 359874144. Its totient is φ = 60930816.

The previous prime is 161847817. The next prime is 161847841. The reversal of 161847820 is 28748161.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 161847820.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 237672 + ... + 238351.

It is an arithmetic number, because the mean of its divisors is an integer number (14994756).

Almost surely, 2^161847820 is an apocalyptic number.

161847820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161847820 is an abundant number, since it is smaller than the sum of its proper divisors (198026324).

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

161847820 is a wasteful number, since it uses less digits than its factorization.

161847820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 476049 (or 476047 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 161847820 is about 12721.9424617469. The cubic root of 161847820 is about 544.9654272040.

The spelling of 161847820 in words is "one hundred sixty-one million, eight hundred forty-seven thousand, eight hundred twenty".