213655780 has 24 divisors (see below), whose sum is σ = 483191352. Its totient is φ = 78888192.

The previous prime is 213655727. The next prime is 213655787. The reversal of 213655780 is 87556312.

213655780 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 729316 + 212926464 = 854^2 + 14592^2 .

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (213655787) 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, 410617 + ... + 411136.

It is an arithmetic number, because the mean of its divisors is an integer number (20132973).

Almost surely, 2^213655780 is an apocalyptic number.

213655780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213655780 is an abundant number, since it is smaller than the sum of its proper divisors (269535572).

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

213655780 is a wasteful number, since it uses less digits than its factorization.

213655780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821775 (or 821773 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 37.

The square root of 213655780 is about 14616.9689060352. The cubic root of 213655780 is about 597.8215259164.

The spelling of 213655780 in words is "two hundred thirteen million, six hundred fifty-five thousand, seven hundred eighty".