121739 has 8 divisors (see below), whose sum is σ = 130560. Its totient is φ = 113256.

The previous prime is 121727. The next prime is 121763. The reversal of 121739 is 937121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121739 - 2¹² = 117643 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121789) 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 7 ways as a sum of consecutive naturals, for example, 1502 + ... + 1580.

It is an arithmetic number, because the mean of its divisors is an integer number (16320).

2¹²¹⁷³⁹ is an apocalyptic number.

121739 is a deficient number, since it is larger than the sum of its proper divisors (8821).

121739 is an equidigital number, since it uses as much as digits as its factorization.

121739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169.

The product of its digits is 378, while the sum is 23.

The square root of 121739 is about 348.9111634786. The cubic root of 121739 is about 49.5613632079.

The spelling of 121739 in words is "one hundred twenty-one thousand, seven hundred thirty-nine".