2661801870 has 128 divisors (see below), whose sum is σ = 7884011520. Its totient is φ = 560079360.

The previous prime is 2661801823. The next prime is 2661801889. The reversal of 2661801870 is 781081662.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1197360 + ... + 1199580.

It is an arithmetic number, because the mean of its divisors is an integer number (61593840).

Almost surely, 2^2661801870 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2661801870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3942005760).

2661801870 is an abundant number, since it is smaller than the sum of its proper divisors (5222209650).

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

2661801870 is a wasteful number, since it uses less digits than its factorization.

2661801870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2690.

The product of its (nonzero) digits is 32256, while the sum is 39.

The square root of 2661801870 is about 51592.6532560596. The cubic root of 2661801870 is about 1385.8787699875.

The spelling of 2661801870 in words is "two billion, six hundred sixty-one million, eight hundred one thousand, eight hundred seventy".