2654551781 has 4 divisors (see below), whose sum is σ = 3033773472. Its totient is φ = 2275330092.

The previous prime is 2654551771. The next prime is 2654551811. The reversal of 2654551781 is 1871554562.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1871554562 = 2 ⋅935777281.

It is a de Polignac number, because none of the positive numbers 2^k-2654551781 is a prime.

It is a super-2 number, since 2×2654551781² = 14093290316020543922, 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 (2654551721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189610835 + ... + 189610848.

It is an arithmetic number, because the mean of its divisors is an integer number (758443368).

Almost surely, 2^2654551781 is an apocalyptic number.

It is an amenable number.

2654551781 is a deficient number, since it is larger than the sum of its proper divisors (379221691).

2654551781 is an equidigital number, since it uses as much as digits as its factorization.

2654551781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379221690.

The product of its digits is 336000, while the sum is 44.

The square root of 2654551781 is about 51522.3425418527. The cubic root of 2654551781 is about 1384.6193623546.

The spelling of 2654551781 in words is "two billion, six hundred fifty-four million, five hundred fifty-one thousand, seven hundred eighty-one".