25554899881 has 27 divisors (see below), whose sum is σ = 30524666277. Its totient is φ = 21331584960.

The previous prime is 25554899861. The next prime is 25554899893. The reversal of 25554899881 is 18899845552.

The square root of 25554899881 is 159859.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 19200259225 + 6354640656 = 138565^2 + 79716^2 .

It is not a de Polignac number, because 25554899881 - 2¹³ = 25554891689 is a prime.

It is a super-2 number, since 2×25554899881² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25554899861) 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 26 ways as a sum of consecutive naturals, for example, 45879255 + ... + 45879811.

Almost surely, 2^25554899881 is an apocalyptic number.

25554899881 is the 159859-th square number.

25554899881 is the 79930-th centered octagonal number.

It is an amenable number.

25554899881 is a deficient number, since it is larger than the sum of its proper divisors (4969766396).

25554899881 is an frugal number, since it uses more digits than its factorization.

25554899881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1210 (or 605 counting only the distinct ones).

The product of its digits is 41472000, while the sum is 64.

Multiplying 25554899881 by its sum of digits (64), we get a square (1635513592384 = 1278872²).

The spelling of 25554899881 in words is "twenty-five billion, five hundred fifty-four million, eight hundred ninety-nine thousand, eight hundred eighty-one".