213903978 has 8 divisors (see below), whose sum is σ = 427807968. Its totient is φ = 71301324.

The previous prime is 213903959. The next prime is 213904001. The reversal of 213903978 is 879309312.

It is a sphenic number, since it is the product of 3 distinct primes.

213903978 is an admirable number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17825326 + ... + 17825337.

It is an arithmetic number, because the mean of its divisors is an integer number (53475996).

Almost surely, 2^213903978 is an apocalyptic number.

213903978 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

213903978 is a wasteful number, since it uses less digits than its factorization.

213903978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35650668.

The product of its (nonzero) digits is 81648, while the sum is 42.

The square root of 213903978 is about 14625.4565056958. The cubic root of 213903978 is about 598.0529272364.

The spelling of 213903978 in words is "two hundred thirteen million, nine hundred three thousand, nine hundred seventy-eight".