642451824 has 200 divisors, whose sum is σ = 2218191360. Its totient is φ = 175519872.

The previous prime is 642451813. The next prime is 642451871. The reversal of 642451824 is 428154246.

642451824 is a `hidden beast` number, since 642 + 4 + 5 + 1 + 8 + 2 + 4 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 207117 + ... + 210195.

Almost surely, 2^642451824 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642451824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1109095680).

642451824 is an abundant number, since it is smaller than the sum of its proper divisors (1575739536).

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

642451824 is a wasteful number, since it uses less digits than its factorization.

642451824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3129 (or 3114 counting only the distinct ones).

The product of its digits is 61440, while the sum is 36.

The square root of 642451824 is about 25346.6333859154. The cubic root of 642451824 is about 862.8729517530.

The spelling of 642451824 in words is "six hundred forty-two million, four hundred fifty-one thousand, eight hundred twenty-four".