121940551 has 4 divisors (see below), whose sum is σ = 124007400. Its totient is φ = 119873704.

The previous prime is 121940527. The next prime is 121940573. The reversal of 121940551 is 155049121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 155049121 = 109 ⋅1422469.

It is a cyclic number.

It is not a de Polignac number, because 121940551 - 2¹⁵ = 121907783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121940051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1033336 + ... + 1033453.

It is an arithmetic number, because the mean of its divisors is an integer number (31001850).

Almost surely, 2^121940551 is an apocalyptic number.

121940551 is a deficient number, since it is larger than the sum of its proper divisors (2066849).

121940551 is an equidigital number, since it uses as much as digits as its factorization.

121940551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066848.

The product of its (nonzero) digits is 1800, while the sum is 28.

The square root of 121940551 is about 11042.6695594861. The cubic root of 121940551 is about 495.8869937986.

Adding to 121940551 its reverse (155049121), we get a palindrome (276989672).

The spelling of 121940551 in words is "one hundred twenty-one million, nine hundred forty thousand, five hundred fifty-one".