2861689428 has 72 divisors (see below), whose sum is σ = 7847192808. Its totient is φ = 874073088.

The previous prime is 2861689421. The next prime is 2861689471. The reversal of 2861689428 is 8249861682.

It can be written as a sum of positive squares in 4 ways, for example, as 559417104 + 2302272324 = 23652^2 + 47982^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2861689421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41800 + ... + 86432.

It is an arithmetic number, because the mean of its divisors is an integer number (108988789).

Almost surely, 2^2861689428 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 2861689428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3923596404).

2861689428 is an abundant number, since it is smaller than the sum of its proper divisors (4985503380).

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

2861689428 is a wasteful number, since it uses less digits than its factorization.

2861689428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44793 (or 44788 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 54.

The square root of 2861689428 is about 53494.7607528064. The cubic root of 2861689428 is about 1419.7356890851.

The spelling of 2861689428 in words is "two billion, eight hundred sixty-one million, six hundred eighty-nine thousand, four hundred twenty-eight".