121686747 has 48 divisors (see below), whose sum is σ = 208871712. Its totient is φ = 62415360.

The previous prime is 121686739. The next prime is 121686751. The reversal of 121686747 is 747686121.

It is not a de Polignac number, because 121686747 - 2³ = 121686739 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 121686699 and 121686708.

It is not an unprimeable number, because it can be changed into a prime (121686737) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 69847 + ... + 71567.

It is an arithmetic number, because the mean of its divisors is an integer number (4351494).

Almost surely, 2^121686747 is an apocalyptic number.

121686747 is a deficient number, since it is larger than the sum of its proper divisors (87184965).

121686747 is a wasteful number, since it uses less digits than its factorization.

121686747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1788 (or 1781 counting only the distinct ones).

The product of its digits is 112896, while the sum is 42.

The square root of 121686747 is about 11031.1716059537. The cubic root of 121686747 is about 495.5427125841.

It can be divided in two parts, 12168 and 6747, that added together give a triangular number (18915 = T₁₉₄).

The spelling of 121686747 in words is "one hundred twenty-one million, six hundred eighty-six thousand, seven hundred forty-seven".