121596781 has 4 divisors (see below), whose sum is σ = 121947552. Its totient is φ = 121246012.

The previous prime is 121596779. The next prime is 121596799. The reversal of 121596781 is 187695121.

It is a happy number.

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 121596781 - 2¹ = 121596779 is a prime.

It is a super-2 number, since 2×121596781² = 29571554299123922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121596731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174865 + ... + 175558.

It is an arithmetic number, because the mean of its divisors is an integer number (30486888).

Almost surely, 2^121596781 is an apocalyptic number.

It is an amenable number.

121596781 is a deficient number, since it is larger than the sum of its proper divisors (350771).

121596781 is an equidigital number, since it uses as much as digits as its factorization.

121596781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350770.

The product of its digits is 30240, while the sum is 40.

The square root of 121596781 is about 11027.0930439532. The cubic root of 121596781 is about 495.4205601774.

The spelling of 121596781 in words is "one hundred twenty-one million, five hundred ninety-six thousand, seven hundred eighty-one".