121097781 has 32 divisors (see below), whose sum is σ = 210586880. Its totient is φ = 67324608.

The previous prime is 121097771. The next prime is 121097797. The reversal of 121097781 is 187790121.

It is not a de Polignac number, because 121097781 - 2⁷ = 121097653 is a prime.

It is a super-2 number, since 2×121097781² = 29329345126247922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121097741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1666 + ... + 15651.

It is an arithmetic number, because the mean of its divisors is an integer number (6580840).

Almost surely, 2^121097781 is an apocalyptic number.

It is an amenable number.

121097781 is a deficient number, since it is larger than the sum of its proper divisors (89489099).

121097781 is a wasteful number, since it uses less digits than its factorization.

121097781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17370 (or 17364 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 36.

The square root of 121097781 is about 11004.4436933450. The cubic root of 121097781 is about 494.7419407874.

The spelling of 121097781 in words is "one hundred twenty-one million, ninety-seven thousand, seven hundred eighty-one".