642636231 has 16 divisors (see below), whose sum is σ = 885163008. Its totient is φ = 414288000.

The previous prime is 642636229. The next prime is 642636233. The reversal of 642636231 is 132636246.

It is an interprime number because it is at equal distance from previous prime (642636229) and next prime (642636233).

It is not a de Polignac number, because 642636231 - 2¹ = 642636229 is a prime.

It is a super-2 number, since 2×642636231² = 825962650787770722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 642636192 and 642636201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642636233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 228031 + ... + 230831.

It is an arithmetic number, because the mean of its divisors is an integer number (55322688).

Almost surely, 2^642636231 is an apocalyptic number.

642636231 is a deficient number, since it is larger than the sum of its proper divisors (242526777).

642636231 is a wasteful number, since it uses less digits than its factorization.

642636231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5302.

The product of its digits is 31104, while the sum is 33.

The square root of 642636231 is about 25350.2708269557. The cubic root of 642636231 is about 862.9555024774.

The spelling of 642636231 in words is "six hundred forty-two million, six hundred thirty-six thousand, two hundred thirty-one".