261121404 has 24 divisors (see below), whose sum is σ = 612021760. Its totient is φ = 86649264.

The previous prime is 261121379. The next prime is 261121429. The reversal of 261121404 is 404121162.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (261121379) and next prime (261121429).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46114 + ... + 51465.

Almost surely, 2^261121404 is an apocalyptic number.

It is an amenable number.

261121404 is an abundant number, since it is smaller than the sum of its proper divisors (350900356).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261121404 is a wasteful number, since it uses less digits than its factorization.

261121404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97809 (or 97807 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 261121404 is about 16159.2513440444. The cubic root of 261121404 is about 639.1667247976.

Adding to 261121404 its reverse (404121162), we get a palindrome (665242566).

The spelling of 261121404 in words is "two hundred sixty-one million, one hundred twenty-one thousand, four hundred four".