1025234261561 has 4 divisors (see below), whose sum is σ = 1029711267300. Its totient is φ = 1020757255824.

The previous prime is 1025234261551. The next prime is 1025234261581. The reversal of 1025234261561 is 1651624325201.

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 703795155625 + 321439105936 = 838925^2 + 566956^2 .

It is a cyclic number.

It is not a de Polignac number, because 1025234261561 - 2²⁶ = 1025167152697 is a prime.

It is a super-2 number, since 2×1025234261561² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1025234261551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2238502526 + ... + 2238502983.

It is an arithmetic number, because the mean of its divisors is an integer number (257427816825).

Almost surely, 2^{1025234261561} is an apocalyptic number.

It is an amenable number.

1025234261561 is a deficient number, since it is larger than the sum of its proper divisors (4477005739).

1025234261561 is an equidigital number, since it uses as much as digits as its factorization.

1025234261561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4477005738.

The product of its (nonzero) digits is 86400, while the sum is 38.

Adding to 1025234261561 its reverse (1651624325201), we get a palindrome (2676858586762).

The spelling of 1025234261561 in words is "one trillion, twenty-five billion, two hundred thirty-four million, two hundred sixty-one thousand, five hundred sixty-one".