642161440 has 48 divisors (see below), whose sum is σ = 1519439040. Its totient is φ = 256469760.

The previous prime is 642161419. The next prime is 642161447. The reversal of 642161440 is 44161246.

It is a junction number, because it is equal to n+sod(n) for n = 642161399 and 642161408.

It is not an unprimeable number, because it can be changed into a prime (642161447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115525 + ... + 120955.

It is an arithmetic number, because the mean of its divisors is an integer number (31654980).

Almost surely, 2^642161440 is an apocalyptic number.

It is an amenable number.

642161440 is an abundant number, since it is smaller than the sum of its proper divisors (877277600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642161440 is a wasteful number, since it uses less digits than its factorization.

642161440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6185 (or 6177 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 642161440 is about 25340.9044826739. The cubic root of 642161440 is about 862.7429278609.

It can be divided in two parts, 64216 and 1440, that added together give a palindrome (65656).

The spelling of 642161440 in words is "six hundred forty-two million, one hundred sixty-one thousand, four hundred forty".