121779261 has 8 divisors (see below), whose sum is σ = 180413760. Its totient is φ = 81186156.

The previous prime is 121779233. The next prime is 121779263. The reversal of 121779261 is 162977121.

It is a happy number.

It is not a de Polignac number, because 121779261 - 2⁶ = 121779197 is a prime.

It is a super-2 number, since 2×121779261² = 29660376819412242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121779263) by changing a digit.

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, 2255145 + ... + 2255198.

It is an arithmetic number, because the mean of its divisors is an integer number (22551720).

Almost surely, 2^121779261 is an apocalyptic number.

It is an amenable number.

121779261 is a deficient number, since it is larger than the sum of its proper divisors (58634499).

121779261 is an equidigital number, since it uses as much as digits as its factorization.

121779261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4510352 (or 4510346 counting only the distinct ones).

The product of its digits is 10584, while the sum is 36.

The square root of 121779261 is about 11035.3641081751. The cubic root of 121779261 is about 495.6682617957.

The spelling of 121779261 in words is "one hundred twenty-one million, seven hundred seventy-nine thousand, two hundred sixty-one".