215161020 has 72 divisors (see below), whose sum is σ = 654776304. Its totient is φ = 57189888.

The previous prime is 215161013. The next prime is 215161069. The reversal of 215161020 is 20161512.

215161020 is a `hidden beast` number, since 2 + 1 + 51 + 610 + 2 + 0 = 666.

215161020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 215160984 and 215161002.

It is a congruent number.

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, 58887 + ... + 62433.

Almost surely, 2^215161020 is an apocalyptic number.

215161020 is a gapful number since it is divisible by the number (20) 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 215161020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (327388152).

215161020 is an abundant number, since it is smaller than the sum of its proper divisors (439615284).

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

215161020 is a wasteful number, since it uses less digits than its factorization.

215161020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3899 (or 3894 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 215161020 is about 14668.3680073824. The cubic root of 215161020 is about 599.2221587073. Note that the first 3 decimals are identical.

The spelling of 215161020 in words is "two hundred fifteen million, one hundred sixty-one thousand, twenty".