642106379 has 4 divisors (see below), whose sum is σ = 662819520. Its totient is φ = 621393240.

The previous prime is 642106363. The next prime is 642106397. The reversal of 642106379 is 973601246.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 973601246 = 2 ⋅486800623.

It is a cyclic number.

It is not a de Polignac number, because 642106379 - 2⁴ = 642106363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642106319) 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, 10356524 + ... + 10356585.

It is an arithmetic number, because the mean of its divisors is an integer number (165704880).

Almost surely, 2^642106379 is an apocalyptic number.

642106379 is a deficient number, since it is larger than the sum of its proper divisors (20713141).

642106379 is a wasteful number, since it uses less digits than its factorization.

642106379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20713140.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 642106379 is about 25339.8180538061. The cubic root of 642106379 is about 862.7182690326.

The spelling of 642106379 in words is "six hundred forty-two million, one hundred six thousand, three hundred seventy-nine".