900121993 has 2 divisors, whose sum is σ = 900121994. Its totient is φ = 900121992.

The previous prime is 900121987. The next prime is 900122063. The reversal of 900121993 is 399121009.

900121993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 854802169 + 45319824 = 29237^2 + 6732^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-900121993 is a prime.

It is not a weakly prime, because it can be changed into another prime (900121793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 450060996 + 450060997.

It is an arithmetic number, because the mean of its divisors is an integer number (450060997).

Almost surely, 2^900121993 is an apocalyptic number.

It is an amenable number.

900121993 is a deficient number, since it is larger than the sum of its proper divisors (1).

900121993 is an equidigital number, since it uses as much as digits as its factorization.

900121993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 900121993 is about 30002.0331477718. The cubic root of 900121993 is about 965.5330059483.

The spelling of 900121993 in words is "nine hundred million, one hundred twenty-one thousand, nine hundred ninety-three".