213978240 has 512 divisors, whose sum is σ = 910656000. Its totient is φ = 46448640.

The previous prime is 213978239. The next prime is 213978293. The reversal of 213978240 is 42879312.

213978240 is a `hidden beast` number, since 21 + 397 + 8 + 240 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 213978195 and 213978204.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3507810 + ... + 3507870.

It is an arithmetic number, because the mean of its divisors is an integer number (1778625).

Almost surely, 2^213978240 is an apocalyptic number.

213978240 is a gapful number since it is divisible by the number (20) 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 213978240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455328000).

213978240 is an abundant number, since it is smaller than the sum of its proper divisors (696677760).

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

213978240 is a wasteful number, since it uses less digits than its factorization.

213978240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 213978240 is about 14627.9950779319. The cubic root of 213978240 is about 598.1221287978.

The spelling of 213978240 in words is "two hundred thirteen million, nine hundred seventy-eight thousand, two hundred forty".