261121804 has 24 divisors (see below), whose sum is σ = 472606848. Its totient is φ = 126107520.

The previous prime is 261121793. The next prime is 261121823. The reversal of 261121804 is 408121162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74802 + ... + 78214.

It is an arithmetic number, because the mean of its divisors is an integer number (19691952).

Almost surely, 2^261121804 is an apocalyptic number.

It is an amenable number.

261121804 is a deficient number, since it is larger than the sum of its proper divisors (211485044).

261121804 is a wasteful number, since it uses less digits than its factorization.

261121804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4065 (or 4063 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 261121804 is about 16159.2637208507. The cubic root of 261121804 is about 639.1670511676.

Adding to 261121804 its reverse (408121162), we get a palindrome (669242966).

The spelling of 261121804 in words is "two hundred sixty-one million, one hundred twenty-one thousand, eight hundred four".