4651998781 has 4 divisors (see below), whose sum is σ = 4652798364. Its totient is φ = 4651199200.

The previous prime is 4651998719. The next prime is 4651998809. The reversal of 4651998781 is 1878991564.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3282258681 + 1369740100 = 57291^2 + 37010^2 .

It is a cyclic number.

It is not a de Polignac number, because 4651998781 - 2²⁷ = 4517781053 is a prime.

It is a super-2 number, since 2×4651998781² = 43282185316850971922, 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 (4651998181) 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, 391000 + ... + 402721.

It is an arithmetic number, because the mean of its divisors is an integer number (1163199591).

Almost surely, 2^4651998781 is an apocalyptic number.

It is an amenable number.

4651998781 is a deficient number, since it is larger than the sum of its proper divisors (799583).

4651998781 is an equidigital number, since it uses as much as digits as its factorization.

4651998781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 799582.

The product of its digits is 4354560, while the sum is 58.

The square root of 4651998781 is about 68205.5626836990. The cubic root of 4651998781 is about 1669.3466531248.

The spelling of 4651998781 in words is "four billion, six hundred fifty-one million, nine hundred ninety-eight thousand, seven hundred eighty-one".