213497681820 has 48 divisors (see below), whose sum is σ = 598189390848. Its totient is φ = 56895012160.

The previous prime is 213497681819. The next prime is 213497681849. The reversal of 213497681820 is 28186794312.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1086804 + ... + 1268123.

It is an arithmetic number, because the mean of its divisors is an integer number (12462278976).

Almost surely, 2^213497681820 is an apocalyptic number.

213497681820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213497681820 is an abundant number, since it is smaller than the sum of its proper divisors (384691709028).

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

213497681820 is a wasteful number, since it uses less digits than its factorization.

213497681820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2356450 (or 2356448 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 51.

The spelling of 213497681820 in words is "two hundred thirteen billion, four hundred ninety-seven million, six hundred eighty-one thousand, eight hundred twenty".