642975853 has 8 divisors (see below), whose sum is σ = 733167288. Its totient is φ = 558603264.

The previous prime is 642975847. The next prime is 642975859. The reversal of 642975853 is 358579246.

It is an interprime number because it is at equal distance from previous prime (642975847) and next prime (642975859).

It can be written as a sum of positive squares in 4 ways, for example, as 227346084 + 415629769 = 15078^2 + 20387^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 642975853 - 2²¹ = 640878701 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 642975797 and 642975806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642975859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1454476 + ... + 1454917.

It is an arithmetic number, because the mean of its divisors is an integer number (91645911).

Almost surely, 2^642975853 is an apocalyptic number.

It is an amenable number.

642975853 is a deficient number, since it is larger than the sum of its proper divisors (90191435).

642975853 is a wasteful number, since it uses less digits than its factorization.

642975853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2909423.

The product of its digits is 1814400, while the sum is 49.

The square root of 642975853 is about 25356.9685293806. The cubic root of 642975853 is about 863.1074946651.

The spelling of 642975853 in words is "six hundred forty-two million, nine hundred seventy-five thousand, eight hundred fifty-three".