216515402 has 4 divisors (see below), whose sum is σ = 324773106. Its totient is φ = 108257700.

The previous prime is 216515381. The next prime is 216515407. The reversal of 216515402 is 204515612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 125865961 + 90649441 = 11219^2 + 9521^2 .

It is not an unprimeable number, because it can be changed into a prime (216515407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54128849 + ... + 54128852.

Almost surely, 2^216515402 is an apocalyptic number.

216515402 is a deficient number, since it is larger than the sum of its proper divisors (108257704).

216515402 is a wasteful number, since it uses less digits than its factorization.

216515402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108257703.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 216515402 is about 14714.4623415197. The cubic root of 216515402 is about 600.4768450051.

The spelling of 216515402 in words is "two hundred sixteen million, five hundred fifteen thousand, four hundred two".