642436 has 12 divisors (see below), whose sum is σ = 1173312. Its totient is φ = 307208.

The previous prime is 642427. The next prime is 642457. The reversal of 642436 is 634246.

It is a super-3 number, since 3×642436³ = 795446294159333568, which contains 333 as substring.

It is an Ulam number.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 642436.

It is an unprimeable number.

642436 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3400 + ... + 3583.

It is an arithmetic number, because the mean of its divisors is an integer number (97776).

2⁶⁴²⁴³⁶ is an apocalyptic number.

It is an amenable number.

642436 is a deficient number, since it is larger than the sum of its proper divisors (530876).

642436 is a wasteful number, since it uses less digits than its factorization.

642436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7010 (or 7008 counting only the distinct ones).

The product of its digits is 3456, while the sum is 25.

The square root of 642436 is about 801.5210539967. The cubic root of 642436 is about 86.2865867324.

Subtracting from 642436 its sum of digits (25), we obtain a triangular number (642411 = T₁₁₃₃).

It can be divided in two parts, 64 and 2436, that added together give a square (2500 = 50²).

The spelling of 642436 in words is "six hundred forty-two thousand, four hundred thirty-six".