2540404251 has 24 divisors (see below), whose sum is σ = 4574928384. Its totient is φ = 1319690160.

The previous prime is 2540404159. The next prime is 2540404259. The reversal of 2540404251 is 1524040452.

2540404251 is a `hidden beast` number, since 2 + 5 + 4 + 0 + 404 + 251 = 666.

It is not a de Polignac number, because 2540404251 - 2¹⁷ = 2540273179 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2540404259) 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, 1832211 + ... + 1833596.

It is an arithmetic number, because the mean of its divisors is an integer number (190622016).

Almost surely, 2^2540404251 is an apocalyptic number.

2540404251 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

2540404251 is a deficient number, since it is larger than the sum of its proper divisors (2034524133).

2540404251 is a wasteful number, since it uses less digits than its factorization.

2540404251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3665831 (or 3665828 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

The square root of 2540404251 is about 50402.4230667534. The cubic root of 2540404251 is about 1364.4813696103.

The spelling of 2540404251 in words is "two billion, five hundred forty million, four hundred four thousand, two hundred fifty-one".