642272064461 has 4 divisors (see below), whose sum is σ = 642274764924. Its totient is φ = 642269364000.

The previous prime is 642272064439. The next prime is 642272064493. The reversal of 642272064461 is 164460272246.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 164460272246 = 2 ⋅82230136123.

It can be written as a sum of positive squares in 2 ways, for example, as 133667747236 + 508604317225 = 365606^2 + 713165^2 .

It is a cyclic number.

It is not a de Polignac number, because 642272064461 - 2¹⁸ = 642271802317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642272064961) 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, 954890 + ... + 1482011.

It is an arithmetic number, because the mean of its divisors is an integer number (160568691231).

Almost surely, 2^642272064461 is an apocalyptic number.

It is an amenable number.

642272064461 is a deficient number, since it is larger than the sum of its proper divisors (2700463).

642272064461 is a wasteful number, since it uses less digits than its factorization.

642272064461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2700462.

The product of its (nonzero) digits is 774144, while the sum is 44.

The spelling of 642272064461 in words is "six hundred forty-two billion, two hundred seventy-two million, sixty-four thousand, four hundred sixty-one".