42641551638 has 96 divisors (see below), whose sum is σ = 110482384896. Its totient is φ = 11621548224.

The previous prime is 42641551609. The next prime is 42641551649. The reversal of 42641551638 is 83615514624.

42641551638 is a `hidden beast` number, since 4 + 2 + 6 + 4 + 1 + 5 + 5 + 1 + 638 = 666.

42641551638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 42641551593 and 42641551602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1043520 + ... + 1083612.

It is an arithmetic number, because the mean of its divisors is an integer number (1150858176).

Almost surely, 2^42641551638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42641551638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55241192448).

42641551638 is an abundant number, since it is smaller than the sum of its proper divisors (67840833258).

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

42641551638 is a wasteful number, since it uses less digits than its factorization.

42641551638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40498 (or 40495 counting only the distinct ones).

The product of its digits is 691200, while the sum is 45.

The spelling of 42641551638 in words is "forty-two billion, six hundred forty-one million, five hundred fifty-one thousand, six hundred thirty-eight".