268121861 has 4 divisors (see below), whose sum is σ = 306424992. Its totient is φ = 229818732.

The previous prime is 268121851. The next prime is 268121891. The reversal of 268121861 is 168121862.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 268121861 - 2¹⁴ = 268105477 is a prime.

It is a super-2 number, since 2×268121861² = 143778664692206642, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (268121851) 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, 19151555 + ... + 19151568.

It is an arithmetic number, because the mean of its divisors is an integer number (76606248).

Almost surely, 2^268121861 is an apocalyptic number.

It is an amenable number.

268121861 is a deficient number, since it is larger than the sum of its proper divisors (38303131).

268121861 is an equidigital number, since it uses as much as digits as its factorization.

268121861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38303130.

The product of its digits is 9216, while the sum is 35.

The square root of 268121861 is about 16374.4270434113. The cubic root of 268121861 is about 644.8282787055.

Subtracting from 268121861 its reverse (168121862), we obtain a palindrome (99999999).

It can be divided in two parts, 2681 and 21861, that added together give a palindrome (24542).

The spelling of 268121861 in words is "two hundred sixty-eight million, one hundred twenty-one thousand, eight hundred sixty-one".