121891851 has 8 divisors (see below), whose sum is σ = 180580560. Its totient is φ = 81261216.

The previous prime is 121891837. The next prime is 121891867. The reversal of 121891851 is 158198121.

It is not a de Polignac number, because 121891851 - 2⁶ = 121891787 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121891831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2257230 + ... + 2257283.

It is an arithmetic number, because the mean of its divisors is an integer number (22572570).

Almost surely, 2^121891851 is an apocalyptic number.

121891851 is a deficient number, since it is larger than the sum of its proper divisors (58688709).

121891851 is an equidigital number, since it uses as much as digits as its factorization.

121891851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4514522 (or 4514516 counting only the distinct ones).

The product of its digits is 5760, while the sum is 36.

The square root of 121891851 is about 11040.4642565428. The cubic root of 121891851 is about 495.8209700626.

The spelling of 121891851 in words is "one hundred twenty-one million, eight hundred ninety-one thousand, eight hundred fifty-one".