921090101 has 4 divisors (see below), whose sum is σ = 921848172. Its totient is φ = 920332032.

The previous prime is 921090097. The next prime is 921090187. The reversal of 921090101 is 101090129.

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 441042001 + 480048100 = 21001^2 + 21910^2 .

It is a cyclic number.

It is not a de Polignac number, because 921090101 - 2² = 921090097 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (921093101) 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, 377210 + ... + 379643.

It is an arithmetic number, because the mean of its divisors is an integer number (230462043).

Almost surely, 2^921090101 is an apocalyptic number.

It is an amenable number.

921090101 is a deficient number, since it is larger than the sum of its proper divisors (758071).

921090101 is a wasteful number, since it uses less digits than its factorization.

921090101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 758070.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 921090101 is about 30349.4662391285. The cubic root of 921090101 is about 972.9728122981.

The spelling of 921090101 in words is "nine hundred twenty-one million, ninety thousand, one hundred one".