642240187 has 8 divisors (see below), whose sum is σ = 647628800. Its totient is φ = 636862824.

The previous prime is 642240163. The next prime is 642240197. The reversal of 642240187 is 781042246.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642240187 is a prime.

It is not an unprimeable number, because it can be changed into a prime (642240197) 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, 142198 + ... + 146644.

It is an arithmetic number, because the mean of its divisors is an integer number (80953600).

Almost surely, 2^642240187 is an apocalyptic number.

642240187 is a deficient number, since it is larger than the sum of its proper divisors (5388613).

642240187 is a wasteful number, since it uses less digits than its factorization.

642240187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5625.

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 642240187 is about 25342.4581877923. The cubic root of 642240187 is about 862.7781919115.

The spelling of 642240187 in words is "six hundred forty-two million, two hundred forty thousand, one hundred eighty-seven".