213987406 has 4 divisors (see below), whose sum is σ = 320981112. Its totient is φ = 106993702.

The previous prime is 213987373. The next prime is 213987427. The reversal of 213987406 is 604789312.

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

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53496850 + ... + 53496853.

It is an arithmetic number, because the mean of its divisors is an integer number (80245278).

Almost surely, 2^213987406 is an apocalyptic number.

213987406 is a deficient number, since it is larger than the sum of its proper divisors (106993706).

213987406 is a wasteful number, since it uses less digits than its factorization.

213987406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106993705.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 213987406 is about 14628.3083779363. The cubic root of 213987406 is about 598.1306690886.

The spelling of 213987406 in words is "two hundred thirteen million, nine hundred eighty-seven thousand, four hundred six".