121021693 has 4 divisors (see below), whose sum is σ = 130331068. Its totient is φ = 111712320.

The previous prime is 121021687. The next prime is 121021717. The reversal of 121021693 is 396120121.

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

It can be written as a sum of positive squares in 2 ways, for example, as 39967684 + 81054009 = 6322^2 + 9003^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121021693 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 (121021603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4654668 + ... + 4654693.

It is an arithmetic number, because the mean of its divisors is an integer number (32582767).

Almost surely, 2^121021693 is an apocalyptic number.

121021693 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

121021693 is a deficient number, since it is larger than the sum of its proper divisors (9309375).

121021693 is an equidigital number, since it uses as much as digits as its factorization.

121021693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9309374.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 121021693 is about 11000.9860012637. The cubic root of 121021693 is about 494.6383005407.

The spelling of 121021693 in words is "one hundred twenty-one million, twenty-one thousand, six hundred ninety-three".