861888042 has 24 divisors (see below), whose sum is σ = 1869025860. Its totient is φ = 287049600.

The previous prime is 861888037. The next prime is 861888109. The reversal of 861888042 is 240888168.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 767234601 + 94653441 = 27699^2 + 9729^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1684 + ... + 41552.

Almost surely, 2^861888042 is an apocalyptic number.

861888042 is an abundant number, since it is smaller than the sum of its proper divisors (1007137818).

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

861888042 is a wasteful number, since it uses less digits than its factorization.

861888042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41078 (or 41075 counting only the distinct ones).

The product of its (nonzero) digits is 196608, while the sum is 45.

The square root of 861888042 is about 29357.9297975862. The cubic root of 861888042 is about 951.6639506951.

The spelling of 861888042 in words is "eight hundred sixty-one million, eight hundred eighty-eight thousand, forty-two".