1026511261 has 4 divisors (see below), whose sum is σ = 1045879452. Its totient is φ = 1007143072.

The previous prime is 1026511237. The next prime is 1026511279. The reversal of 1026511261 is 1621156201.

It is a happy number.

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 626751225 + 399760036 = 25035^2 + 19994^2 .

It is a cyclic number.

It is not a de Polignac number, because 1026511261 - 2¹¹ = 1026509213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1026511201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9684016 + ... + 9684121.

It is an arithmetic number, because the mean of its divisors is an integer number (261469863).

Almost surely, 2^1026511261 is an apocalyptic number.

It is an amenable number.

1026511261 is a deficient number, since it is larger than the sum of its proper divisors (19368191).

1026511261 is an equidigital number, since it uses as much as digits as its factorization.

1026511261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19368190.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 1026511261 is about 32039.2144254506. The cubic root of 1026511261 is about 1008.7601231590.

Adding to 1026511261 its reverse (1621156201), we get a palindrome (2647667462).

The spelling of 1026511261 in words is "one billion, twenty-six million, five hundred eleven thousand, two hundred sixty-one".