42640186 has 16 divisors (see below), whose sum is σ = 66251520. Its totient is φ = 20569360.

The previous prime is 42640181. The next prime is 42640201. The reversal of 42640186 is 68104624.

It is a super-2 number, since 2×42640186² = 3636370924229192, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (42640181) 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, 3480 + ... + 9868.

It is an arithmetic number, because the mean of its divisors is an integer number (4140720).

Almost surely, 2^42640186 is an apocalyptic number.

42640186 is a deficient number, since it is larger than the sum of its proper divisors (23611334).

42640186 is a wasteful number, since it uses less digits than its factorization.

42640186 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6509.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 42640186 is about 6529.9453290208. The cubic root of 42640186 is about 349.3598803304.

The spelling of 42640186 in words is "forty-two million, six hundred forty thousand, one hundred eighty-six".