261144899 has 4 divisors (see below), whose sum is σ = 269568960. Its totient is φ = 252720840.

The previous prime is 261144869. The next prime is 261144901. The reversal of 261144899 is 998441162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 998441162 = 2 ⋅499220581.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261144899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261144839) 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, 4211984 + ... + 4212045.

It is an arithmetic number, because the mean of its divisors is an integer number (67392240).

Almost surely, 2^261144899 is an apocalyptic number.

261144899 is a deficient number, since it is larger than the sum of its proper divisors (8424061).

261144899 is an equidigital number, since it uses as much as digits as its factorization.

261144899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8424060.

The product of its digits is 124416, while the sum is 44.

The square root of 261144899 is about 16159.9783106290. The cubic root of 261144899 is about 639.1858943889.

It can be divided in two parts, 26114 and 4899, that added together give a palindrome (31013).

The spelling of 261144899 in words is "two hundred sixty-one million, one hundred forty-four thousand, eight hundred ninety-nine".