216981204 has 24 divisors (see below), whose sum is σ = 552316128. Its totient is φ = 65751840.

The previous prime is 216981203. The next prime is 216981211. The reversal of 216981204 is 402189612.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216981203) 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, 821767 + ... + 822030.

It is an arithmetic number, because the mean of its divisors is an integer number (23013172).

Almost surely, 2^216981204 is an apocalyptic number.

It is an amenable number.

216981204 is an abundant number, since it is smaller than the sum of its proper divisors (335334924).

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

216981204 is a wasteful number, since it uses less digits than its factorization.

216981204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1643815 (or 1643813 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 216981204 is about 14730.2818710302. The cubic root of 216981204 is about 600.9071499958.

The spelling of 216981204 in words is "two hundred sixteen million, nine hundred eighty-one thousand, two hundred four".