2561251767 has 8 divisors (see below), whose sum is σ = 3417314160. Its totient is φ = 1706345280.

The previous prime is 2561251757. The next prime is 2561251787. The reversal of 2561251767 is 7671521652.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2561251767 - 2⁷ = 2561251639 is a prime.

It is a super-2 number, since 2×2561251767² = 13120021227921244578, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561251727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 283792 + ... + 292677.

It is an arithmetic number, because the mean of its divisors is an integer number (427164270).

Almost surely, 2^2561251767 is an apocalyptic number.

2561251767 is a deficient number, since it is larger than the sum of its proper divisors (856062393).

2561251767 is a wasteful number, since it uses less digits than its factorization.

2561251767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577953.

The product of its digits is 176400, while the sum is 42.

The square root of 2561251767 is about 50608.8111597180. The cubic root of 2561251767 is about 1368.2036888701.

The spelling of 2561251767 in words is "two billion, five hundred sixty-one million, two hundred fifty-one thousand, seven hundred sixty-seven".