921012906 has 64 divisors (see below), whose sum is σ = 2056876416. Its totient is φ = 272563200.

The previous prime is 921012901. The next prime is 921012907. The reversal of 921012906 is 609210129.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (921012901) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 982470 + ... + 983406.

It is an arithmetic number, because the mean of its divisors is an integer number (32138694).

Almost surely, 2^921012906 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 921012906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1028438208).

921012906 is an abundant number, since it is smaller than the sum of its proper divisors (1135863510).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

921012906 is a wasteful number, since it uses less digits than its factorization.

921012906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1287.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 921012906 is about 30348.1944438215. The cubic root of 921012906 is about 972.9456304713.

The spelling of 921012906 in words is "nine hundred twenty-one million, twelve thousand, nine hundred six".