161650020 has 72 divisors (see below), whose sum is σ = 526526784. Its totient is φ = 36947904.

The previous prime is 161650019. The next prime is 161650033. The reversal of 161650020 is 20056161.

It is a happy number.

It is a super-2 number, since 2×161650020² = 52261457932000800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24552 + ... + 30431.

It is an arithmetic number, because the mean of its divisors is an integer number (7312872).

Almost surely, 2^161650020 is an apocalyptic number.

161650020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161650020 is an abundant number, since it is smaller than the sum of its proper divisors (364876764).

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

161650020 is a wasteful number, since it uses less digits than its factorization.

161650020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55009 (or 55000 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 161650020 is about 12714.1661150073. The cubic root of 161650020 is about 544.7433294655.

The spelling of 161650020 in words is "one hundred sixty-one million, six hundred fifty thousand, twenty".