42864640 has 208 divisors, whose sum is σ = 132104448. Its totient is φ = 12976128.

The previous prime is 42864631. The next prime is 42864671. The reversal of 42864640 is 4646824.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (208).

It is a junction number, because it is equal to n+sod(n) for n = 42864596 and 42864605.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1863669 + ... + 1863691.

Almost surely, 2^42864640 is an apocalyptic number.

42864640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42864640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66052224).

42864640 is an abundant number, since it is smaller than the sum of its proper divisors (89239808).

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

42864640 is a wasteful number, since it uses less digits than its factorization.

42864640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72 (or 50 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 34.

The square root of 42864640 is about 6547.1092857841. The cubic root of 42864640 is about 349.9718072529.

The spelling of 42864640 in words is "forty-two million, eight hundred sixty-four thousand, six hundred forty".