2143899940 has 72 divisors (see below), whose sum is σ = 5640139512. Its totient is φ = 678504960.

The previous prime is 2143899929. The next prime is 2143899949. The reversal of 2143899940 is 499983412.

It can be written as a sum of positive squares in 4 ways, for example, as 181764324 + 1962135616 = 13482^2 + 44296^2 .

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (2143899949) 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, 71401 + ... + 96880.

It is an arithmetic number, because the mean of its divisors is an integer number (78335271).

Almost surely, 2^2143899940 is an apocalyptic number.

2143899940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2143899940 is an abundant number, since it is smaller than the sum of its proper divisors (3496239572).

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

2143899940 is a wasteful number, since it uses less digits than its factorization.

2143899940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168317 (or 168308 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 49.

The square root of 2143899940 is about 46302.2671151208. The cubic root of 2143899940 is about 1289.4410855203.

The spelling of 2143899940 in words is "two billion, one hundred forty-three million, eight hundred ninety-nine thousand, nine hundred forty".