2561620625726 has 4 divisors (see below), whose sum is σ = 3842430938592. Its totient is φ = 1280810312862.

The previous prime is 2561620625687. The next prime is 2561620625747. The reversal of 2561620625726 is 6275260261652.

It is a semiprime because it is the product of two primes.

It is a super-4 number, since 4×2561620625726⁴ (a number of 51 digits) contains 4444 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640405156430 + ... + 640405156433.

It is an arithmetic number, because the mean of its divisors is an integer number (960607734648).

Almost surely, 2^{2561620625726} is an apocalyptic number.

2561620625726 is a deficient number, since it is larger than the sum of its proper divisors (1280810312866).

2561620625726 is a wasteful number, since it uses less digits than its factorization.

2561620625726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280810312865.

The product of its (nonzero) digits is 3628800, while the sum is 50.

The spelling of 2561620625726 in words is "two trillion, five hundred sixty-one billion, six hundred twenty million, six hundred twenty-five thousand, seven hundred twenty-six".