261051612403 has 4 divisors (see below), whose sum is σ = 261056905560. Its totient is φ = 261046319248.

The previous prime is 261051612361. The next prime is 261051612421. The reversal of 261051612403 is 304216150162.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261051612403 is a prime.

It is a super-2 number, since 2×261051612403² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261051612443) 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, 2571898 + ... + 2671471.

It is an arithmetic number, because the mean of its divisors is an integer number (65264226390).

Almost surely, 2^261051612403 is an apocalyptic number.

261051612403 is a deficient number, since it is larger than the sum of its proper divisors (5293157).

261051612403 is an equidigital number, since it uses as much as digits as its factorization.

261051612403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5293156.

The product of its (nonzero) digits is 8640, while the sum is 31.

Adding to 261051612403 its reverse (304216150162), we get a palindrome (565267762565).

The spelling of 261051612403 in words is "two hundred sixty-one billion, fifty-one million, six hundred twelve thousand, four hundred three".