121778737 has 4 divisors (see below), whose sum is σ = 123320320. Its totient is φ = 120237156.

The previous prime is 121778719. The next prime is 121778807. The reversal of 121778737 is 737877121.

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 121778737 - 2¹⁹ = 121254449 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121778693 and 121778702.

It is not an unprimeable number, because it can be changed into a prime (121778717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 770673 + ... + 770830.

It is an arithmetic number, because the mean of its divisors is an integer number (30830080).

Almost surely, 2^121778737 is an apocalyptic number.

It is an amenable number.

121778737 is a deficient number, since it is larger than the sum of its proper divisors (1541583).

121778737 is an equidigital number, since it uses as much as digits as its factorization.

121778737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1541582.

The product of its digits is 115248, while the sum is 43.

The square root of 121778737 is about 11035.3403662959. The cubic root of 121778737 is about 495.6675508630.

The spelling of 121778737 in words is "one hundred twenty-one million, seven hundred seventy-eight thousand, seven hundred thirty-seven".