121220001 has 24 divisors (see below), whose sum is σ = 200401344. Its totient is φ = 69167520.

The previous prime is 121219999. The next prime is 121220017. The reversal of 121220001 is 100022121.

It is not a de Polignac number, because 121220001 - 2¹ = 121219999 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (121220041) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 73971 + ... + 75591.

It is an arithmetic number, because the mean of its divisors is an integer number (8350056).

Almost surely, 2^121220001 is an apocalyptic number.

It is an amenable number.

121220001 is a deficient number, since it is larger than the sum of its proper divisors (79181343).

121220001 is a wasteful number, since it uses less digits than its factorization.

121220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2821 (or 2818 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 121220001 is about 11009.9955040863. The cubic root of 121220001 is about 494.9083270699.

Adding to 121220001 its reverse (100022121), we get a palindrome (221242122).

The spelling of 121220001 in words is "one hundred twenty-one million, two hundred twenty thousand, one".