121836145 has 4 divisors (see below), whose sum is σ = 146203380. Its totient is φ = 97468912.

The previous prime is 121836131. The next prime is 121836149. The reversal of 121836145 is 541638121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 541638121 = 10463 ⋅51767.

It can be written as a sum of positive squares in 2 ways, for example, as 41679936 + 80156209 = 6456^2 + 8953^2 .

It is a cyclic number.

It is not a de Polignac number, because 121836145 - 2⁷ = 121836017 is a prime.

It is a super-2 number, since 2×121836145² = 29688092456922050, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (121836149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12183610 + ... + 12183619.

It is an arithmetic number, because the mean of its divisors is an integer number (36550845).

Almost surely, 2^121836145 is an apocalyptic number.

It is an amenable number.

121836145 is a deficient number, since it is larger than the sum of its proper divisors (24367235).

121836145 is an equidigital number, since it uses as much as digits as its factorization.

121836145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24367234.

The product of its digits is 5760, while the sum is 31.

The square root of 121836145 is about 11037.9411576616. The cubic root of 121836145 is about 495.7454265613.

The spelling of 121836145 in words is "one hundred twenty-one million, eight hundred thirty-six thousand, one hundred forty-five".