642619 has 4 divisors (see below), whose sum is σ = 651496. Its totient is φ = 633744.

The previous prime is 642613. The next prime is 642623. The reversal of 642619 is 916246.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 916246 = 2 ⋅458123.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642619 is a prime.

It is a super-2 number, since 2×642619² = 825918358322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642613) 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, 4329 + ... + 4474.

It is an arithmetic number, because the mean of its divisors is an integer number (162874).

2⁶⁴²⁶¹⁹ is an apocalyptic number.

642619 is a deficient number, since it is larger than the sum of its proper divisors (8877).

642619 is an equidigital number, since it uses as much as digits as its factorization.

642619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8876.

The product of its digits is 2592, while the sum is 28.

The square root of 642619 is about 801.6352038178. The cubic root of 642619 is about 86.2947789602.

The spelling of 642619 in words is "six hundred forty-two thousand, six hundred nineteen".