261653513323 has 4 divisors (see below), whose sum is σ = 262806172200. Its totient is φ = 260500854448.

The previous prime is 261653513311. The next prime is 261653513339. The reversal of 261653513323 is 323315356162.

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

It is a cyclic number.

It is not a de Polignac number, because 261653513323 - 2⁵ = 261653513291 is a prime.

It is a super-2 number, since 2×261653513323² (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 (261653514323) 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, 576329098 + ... + 576329551.

It is an arithmetic number, because the mean of its divisors is an integer number (65701543050).

Almost surely, 2^261653513323 is an apocalyptic number.

261653513323 is a deficient number, since it is larger than the sum of its proper divisors (1152658877).

261653513323 is a wasteful number, since it uses less digits than its factorization.

261653513323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1152658876.

The product of its digits is 291600, while the sum is 40.

Adding to 261653513323 its reverse (323315356162), we get a palindrome (584968869485).

The spelling of 261653513323 in words is "two hundred sixty-one billion, six hundred fifty-three million, five hundred thirteen thousand, three hundred twenty-three".