2145540020 has 48 divisors (see below), whose sum is σ = 4883220048. Its totient is φ = 787138560.

The previous prime is 2145539987. The next prime is 2145540043. The reversal of 2145540020 is 200455412.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 63808144 + 2081731876 = 7988^2 + 45626^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14540 + ... + 67100.

It is an arithmetic number, because the mean of its divisors is an integer number (101733751).

Almost surely, 2^2145540020 is an apocalyptic number.

2145540020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2145540020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2441610024).

2145540020 is an abundant number, since it is smaller than the sum of its proper divisors (2737680028).

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

2145540020 is a wasteful number, since it uses less digits than its factorization.

2145540020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52740 (or 52738 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 2145540020 is about 46319.9743091466. The cubic root of 2145540020 is about 1289.7698084947.

Adding to 2145540020 its reverse (200455412), we get a palindrome (2345995432).

The spelling of 2145540020 in words is "two billion, one hundred forty-five million, five hundred forty thousand, twenty".