2543557640 has 32 divisors (see below), whose sum is σ = 6163237080. Its totient is φ = 939159552.

The previous prime is 2543557579. The next prime is 2543557661. The reversal of 2543557640 is 467553452.

It can be written as a sum of positive squares in 4 ways, for example, as 1273490596 + 1270067044 = 35686^2 + 35638^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2445209 + ... + 2446248.

Almost surely, 2^2543557640 is an apocalyptic number.

2543557640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2543557640 is an abundant number, since it is smaller than the sum of its proper divisors (3619679440).

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

2543557640 is a wasteful number, since it uses less digits than its factorization.

2543557640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4891481 (or 4891477 counting only the distinct ones).

The product of its (nonzero) digits is 504000, while the sum is 41.

The square root of 2543557640 is about 50433.6954822864. The cubic root of 2543557640 is about 1365.0457104293.

The spelling of 2543557640 in words is "two billion, five hundred forty-three million, five hundred fifty-seven thousand, six hundred forty".