1620018900 has 144 divisors (see below), whose sum is σ = 5271537600. Its totient is φ = 426741120.

The previous prime is 1620018887. The next prime is 1620018919. The reversal of 1620018900 is 98100261.

It is a super-2 number, since 2×1620018900² = 5248922472714420000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 220486 + ... + 227714.

It is an arithmetic number, because the mean of its divisors is an integer number (36607900).

Almost surely, 2^1620018900 is an apocalyptic number.

1620018900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1620018900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2635768800).

1620018900 is an abundant number, since it is smaller than the sum of its proper divisors (3651518700).

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

1620018900 is a wasteful number, since it uses less digits than its factorization.

1620018900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7335 (or 7322 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 1620018900 is about 40249.4583814491. The cubic root of 1620018900 is about 1174.4648596785.

The spelling of 1620018900 in words is "one billion, six hundred twenty million, eighteen thousand, nine hundred".