642170371 has 4 divisors (see below), whose sum is σ = 642411000. Its totient is φ = 641929744.

The previous prime is 642170357. The next prime is 642170377. The reversal of 642170371 is 173071246.

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

It is a cyclic number.

It is not a de Polignac number, because 642170371 - 2⁹ = 642169859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642170377) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116266 + ... + 121663.

It is an arithmetic number, because the mean of its divisors is an integer number (160602750).

Almost surely, 2^642170371 is an apocalyptic number.

642170371 is a deficient number, since it is larger than the sum of its proper divisors (240629).

642170371 is a wasteful number, since it uses less digits than its factorization.

642170371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240628.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 642170371 is about 25341.0806991336. The cubic root of 642170371 is about 862.7469274374.

The spelling of 642170371 in words is "six hundred forty-two million, one hundred seventy thousand, three hundred seventy-one".