42640395840 has 1512 divisors, whose sum is σ = 192755227392. Its totient is φ = 8935557120.

The previous prime is 42640395839. The next prime is 42640395851. The reversal of 42640395840 is 4859304624.

42640395840 is a `hidden beast` number, since 4 + 2 + 64 + 0 + 3 + 9 + 584 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1512).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 1375496625 + ... + 1375496655.

It is an arithmetic number, because the mean of its divisors is an integer number (127483616).

Almost surely, 2^42640395840 is an apocalyptic number.

42640395840 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 42640395840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96377613696).

42640395840 is an abundant number, since it is smaller than the sum of its proper divisors (150114831552).

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

42640395840 is a wasteful number, since it uses less digits than its factorization.

42640395840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The spelling of 42640395840 in words is "forty-two billion, six hundred forty million, three hundred ninety-five thousand, eight hundred forty".