216640254 has 16 divisors (see below), whose sum is σ = 444991248. Its totient is φ = 70261632.

The previous prime is 216640213. The next prime is 216640273. The reversal of 216640254 is 452046612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 487707 + ... + 488150.

It is an arithmetic number, because the mean of its divisors is an integer number (27811953).

Almost surely, 2^216640254 is an apocalyptic number.

216640254 is an abundant number, since it is smaller than the sum of its proper divisors (228350994).

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

216640254 is a wasteful number, since it uses less digits than its factorization.

216640254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 975899.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 216640254 is about 14718.7042228588. The cubic root of 216640254 is about 600.5922429992.

Adding to 216640254 its reverse (452046612), we get a palindrome (668686866).

The spelling of 216640254 in words is "two hundred sixteen million, six hundred forty thousand, two hundred fifty-four".