642667893 has 16 divisors (see below), whose sum is σ = 983408640. Its totient is φ = 365699376.

The previous prime is 642667891. The next prime is 642667897. The reversal of 642667893 is 398766246.

It is a happy number.

It is not a de Polignac number, because 642667893 - 2¹ = 642667891 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642667891) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59005 + ... + 69042.

It is an arithmetic number, because the mean of its divisors is an integer number (61463040).

Almost surely, 2^642667893 is an apocalyptic number.

It is an amenable number.

642667893 is a deficient number, since it is larger than the sum of its proper divisors (340740747).

642667893 is a wasteful number, since it uses less digits than its factorization.

642667893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128296.

The product of its digits is 2612736, while the sum is 51.

The square root of 642667893 is about 25350.8953096335. The cubic root of 642667893 is about 862.9696745430.

The spelling of 642667893 in words is "six hundred forty-two million, six hundred sixty-seven thousand, eight hundred ninety-three".