2554861781 has 4 divisors (see below), whose sum is σ = 2665942752. Its totient is φ = 2443780812.

The previous prime is 2554861763. The next prime is 2554861819. The reversal of 2554861781 is 1871684552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2554861781 is a prime.

It is a super-2 number, since 2×2554861781² = 13054637440028983922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2554861721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55540451 + ... + 55540496.

It is an arithmetic number, because the mean of its divisors is an integer number (666485688).

Almost surely, 2^2554861781 is an apocalyptic number.

It is an amenable number.

2554861781 is a deficient number, since it is larger than the sum of its proper divisors (111080971).

2554861781 is a wasteful number, since it uses less digits than its factorization.

2554861781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111080970.

The product of its digits is 537600, while the sum is 47.

The square root of 2554861781 is about 50545.6405736439. The cubic root of 2554861781 is about 1367.0649119463.

The spelling of 2554861781 in words is "two billion, five hundred fifty-four million, eight hundred sixty-one thousand, seven hundred eighty-one".