213031820 has 24 divisors (see below), whose sum is σ = 447710928. Its totient is φ = 85147200.

The previous prime is 213031813. The next prime is 213031823. The reversal of 213031820 is 28130312.

213031820 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 (20).

It is a junction number, because it is equal to n+sod(n) for n = 213031792 and 213031801.

It is not an unprimeable number, because it can be changed into a prime (213031823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29135 + ... + 35705.

It is an arithmetic number, because the mean of its divisors is an integer number (18654622).

Almost surely, 2^213031820 is an apocalyptic number.

213031820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213031820 is an abundant number, since it is smaller than the sum of its proper divisors (234679108).

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

213031820 is a wasteful number, since it uses less digits than its factorization.

213031820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8201 (or 8199 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 213031820 is about 14595.6096138531. The cubic root of 213031820 is about 597.2389994670.

The spelling of 213031820 in words is "two hundred thirteen million, thirty-one thousand, eight hundred twenty".