42780821834 has 16 divisors (see below), whose sum is σ = 64347969480. Its totient is φ = 21331537920.

The previous prime is 42780821833. The next prime is 42780821849. The reversal of 42780821834 is 43812808724.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 14970256609 + 27810565225 = 122353^2 + 166765^2 .

It is a super-2 number, since 2×42780821834² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (42780821833) 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, 2660282 + ... + 2676314.

Almost surely, 2^42780821834 is an apocalyptic number.

42780821834 is a deficient number, since it is larger than the sum of its proper divisors (21567147646).

42780821834 is a wasteful number, since it uses less digits than its factorization.

42780821834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19625.

The product of its (nonzero) digits is 688128, while the sum is 47.

The spelling of 42780821834 in words is "forty-two billion, seven hundred eighty million, eight hundred twenty-one thousand, eight hundred thirty-four".