121881601 has 4 divisors (see below), whose sum is σ = 122404932. Its totient is φ = 121358272.

The previous prime is 121881581. The next prime is 121881629. The reversal of 121881601 is 106188121.

It is a Cunningham number, because it is equal to 11040²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24760576 + 97121025 = 4976^2 + 9855^2 .

It is a cyclic number.

It is not a de Polignac number, because 121881601 - 2⁵ = 121881569 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121881601.

It is not an unprimeable number, because it can be changed into a prime (121881631) 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, 261316 + ... + 261781.

It is an arithmetic number, because the mean of its divisors is an integer number (30601233).

Almost surely, 2^121881601 is an apocalyptic number.

It is an amenable number.

121881601 is a deficient number, since it is larger than the sum of its proper divisors (523331).

121881601 is an equidigital number, since it uses as much as digits as its factorization.

121881601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523330.

The product of its (nonzero) digits is 768, while the sum is 28.

The square root of 121881601 is about 11040.0000452899. Note that the first 4 decimals coincide. The cubic root of 121881601 is about 495.8070716563.

The spelling of 121881601 in words is "one hundred twenty-one million, eight hundred eighty-one thousand, six hundred one".