216121704 has 64 divisors (see below), whose sum is σ = 555128640. Its totient is φ = 70087680.

The previous prime is 216121691. The next prime is 216121709. The reversal of 216121704 is 407121612.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (216121709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165984 + ... + 167280.

It is an arithmetic number, because the mean of its divisors is an integer number (8673885).

Almost surely, 2^216121704 is an apocalyptic number.

216121704 is a gapful number since it is divisible by the number (24) 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 216121704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (277564320).

216121704 is an abundant number, since it is smaller than the sum of its proper divisors (339006936).

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

216121704 is a wasteful number, since it uses less digits than its factorization.

216121704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1490 (or 1486 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 216121704 is about 14701.0783277962. The cubic root of 216121704 is about 600.1126677309.

The spelling of 216121704 in words is "two hundred sixteen million, one hundred twenty-one thousand, seven hundred four".