642804209493 has 16 divisors (see below), whose sum is σ = 874235635200. Its totient is φ = 420018744816.

The previous prime is 642804209477. The next prime is 642804209497. The reversal of 642804209493 is 394902408246.

It is not a de Polignac number, because 642804209493 - 2⁴ = 642804209477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642804209497) 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, 7995255 + ... + 8075252.

It is an arithmetic number, because the mean of its divisors is an integer number (54639727200).

Almost surely, 2^642804209493 is an apocalyptic number.

It is an amenable number.

642804209493 is a deficient number, since it is larger than the sum of its proper divisors (231431425707).

642804209493 is a wasteful number, since it uses less digits than its factorization.

642804209493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16070776.

The product of its (nonzero) digits is 2985984, while the sum is 51.

The spelling of 642804209493 in words is "six hundred forty-two billion, eight hundred four million, two hundred nine thousand, four hundred ninety-three".