121745 has 8 divisors (see below), whose sum is σ = 157416. Its totient is φ = 89856.

The previous prime is 121727. The next prime is 121763. The reversal of 121745 is 547121.

121745 = 7² + 8² + ... + 71².

It is an interprime number because it is at equal distance from previous prime (121727) and next prime (121763).

It can be written as a sum of positive squares in 4 ways, for example, as 4096 + 117649 = 64^2 + 343^2 .

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

It is not a de Polignac number, because 121745 - 2¹⁰ = 120721 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 872 + ... + 1001.

It is an arithmetic number, because the mean of its divisors is an integer number (19677).

2¹²¹⁷⁴⁵ is an apocalyptic number.

It is an amenable number.

121745 is a deficient number, since it is larger than the sum of its proper divisors (35671).

121745 is a wasteful number, since it uses less digits than its factorization.

121745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1891.

The product of its digits is 280, while the sum is 20.

The square root of 121745 is about 348.9197615498. The cubic root of 121745 is about 49.5621774178.

Adding to 121745 its reverse (547121), we get a palindrome (668866).

The spelling of 121745 in words is "one hundred twenty-one thousand, seven hundred forty-five".