121620381 has 4 divisors (see below), whose sum is σ = 162160512. Its totient is φ = 81080252.

The previous prime is 121620379. The next prime is 121620419. The reversal of 121620381 is 183026121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 183026121 = 3 ⋅61008707.

It is a cyclic number.

It is not a de Polignac number, because 121620381 - 2¹ = 121620379 is a prime.

It is a super-2 number, since 2×121620381² = 29583034149170322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121620371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20270061 + ... + 20270066.

It is an arithmetic number, because the mean of its divisors is an integer number (40540128).

Almost surely, 2^121620381 is an apocalyptic number.

It is an amenable number.

121620381 is a deficient number, since it is larger than the sum of its proper divisors (40540131).

121620381 is an equidigital number, since it uses as much as digits as its factorization.

121620381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40540130.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 121620381 is about 11028.1630836690. The cubic root of 121620381 is about 495.4526091861.

The spelling of 121620381 in words is "one hundred twenty-one million, six hundred twenty thousand, three hundred eighty-one".