2145255440 has 40 divisors (see below), whose sum is σ = 5015309208. Its totient is φ = 853355520.

The previous prime is 2145255421. The next prime is 2145255443. The reversal of 2145255440 is 445525412.

It can be written as a sum of positive squares in 4 ways, for example, as 2676496 + 2142578944 = 1636^2 + 46288^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 2145255397 and 2145255406.

It is not an unprimeable number, because it can be changed into a prime (2145255443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59597 + ... + 88556.

Almost surely, 2^2145255440 is an apocalyptic number.

2145255440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2145255440 is an abundant number, since it is smaller than the sum of its proper divisors (2870053768).

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

2145255440 is a wasteful number, since it uses less digits than its factorization.

2145255440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148347 (or 148341 counting only the distinct ones).

The product of its (nonzero) digits is 32000, while the sum is 32.

The square root of 2145255440 is about 46316.9023143819. The cubic root of 2145255440 is about 1289.7127818382.

The spelling of 2145255440 in words is "two billion, one hundred forty-five million, two hundred fifty-five thousand, four hundred forty".