25542213440 has 28 divisors (see below), whose sum is σ = 60822396516. Its totient is φ = 10216885248.

The previous prime is 25542213427. The next prime is 25542213467. The reversal of 25542213440 is 4431224552.

It can be written as a sum of positive squares in 2 ways, for example, as 7763724544 + 17778488896 = 88112^2 + 133336^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 25542213397 and 25542213406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39909389 + ... + 39910028.

It is an arithmetic number, because the mean of its divisors is an integer number (2172228447).

Almost surely, 2^25542213440 is an apocalyptic number.

25542213440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25542213440 is an abundant number, since it is smaller than the sum of its proper divisors (35280183076).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25542213440 is an equidigital number, since it uses as much as digits as its factorization.

25542213440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79819434 (or 79819424 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 32.

Adding to 25542213440 its reverse (4431224552), we get a palindrome (29973437992).

It can be divided in two parts, 255422 and 13440, that added together give a palindrome (268862).

The spelling of 25542213440 in words is "twenty-five billion, five hundred forty-two million, two hundred thirteen thousand, four hundred forty".