121603591 has 4 divisors (see below), whose sum is σ = 128003800. Its totient is φ = 115203384.

The previous prime is 121603577. The next prime is 121603597. The reversal of 121603591 is 195306121.

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

It is not a de Polignac number, because 121603591 - 2⁷ = 121603463 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121603597) 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, 3200076 + ... + 3200113.

It is an arithmetic number, because the mean of its divisors is an integer number (32000950).

Almost surely, 2^121603591 is an apocalyptic number.

121603591 is a deficient number, since it is larger than the sum of its proper divisors (6400209).

121603591 is an equidigital number, since it uses as much as digits as its factorization.

121603591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6400208.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 121603591 is about 11027.4018245460. The cubic root of 121603591 is about 495.4298086432.

It can be divided in two parts, 12160 and 3591, that added together give a palindrome (15751).

The spelling of 121603591 in words is "one hundred twenty-one million, six hundred three thousand, five hundred ninety-one".