2545136640 has 660 divisors, whose sum is σ = 10191824676. Its totient is φ = 605159424.

The previous prime is 2545136639. The next prime is 2545136669. The reversal of 2545136640 is 466315452.

2545136640 is a `hidden beast` number, since 2 + 5 + 4 + 5 + 1 + 3 + 6 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1467196416 + 1077940224 = 38304^2 + 32832^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2545136595 and 2545136604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 133954551 + ... + 133954569.

Almost surely, 2^2545136640 is an apocalyptic number.

2545136640 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 2545136640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5095912338).

2545136640 is an abundant number, since it is smaller than the sum of its proper divisors (7646688036).

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

2545136640 is a wasteful number, since it uses less digits than its factorization.

2545136640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 2545136640 is about 50449.3472703067. The cubic root of 2545136640 is about 1365.3281181984.

The spelling of 2545136640 in words is "two billion, five hundred forty-five million, one hundred thirty-six thousand, six hundred forty".