216405494 has 16 divisors (see below), whose sum is σ = 326678400. Its totient is φ = 107515584.

The previous prime is 216405493. The next prime is 216405517. The reversal of 216405494 is 494504612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216405493) 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, 380042 + ... + 380610.

It is an arithmetic number, because the mean of its divisors is an integer number (20417400).

Almost surely, 2^216405494 is an apocalyptic number.

216405494 is a deficient number, since it is larger than the sum of its proper divisors (110272906).

216405494 is a wasteful number, since it uses less digits than its factorization.

216405494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1447.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 216405494 is about 14710.7271744126. The cubic root of 216405494 is about 600.3752227050.

The spelling of 216405494 in words is "two hundred sixteen million, four hundred five thousand, four hundred ninety-four".