912821 has 12 divisors (see below), whose sum is σ = 1144332. Its totient is φ = 721728.

The previous prime is 912809. The next prime is 912823. The reversal of 912821 is 128219.

It can be written as a sum of positive squares in 2 ways, for example, as 442225 + 470596 = 665^2 + 686^2 .

It is a de Polignac number, because none of the positive numbers 2^k-912821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (912823) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 80 + ... + 1353.

It is an arithmetic number, because the mean of its divisors is an integer number (95361).

2⁹¹²⁸²¹ is an apocalyptic number.

912821 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

It is an amenable number.

912821 is a deficient number, since it is larger than the sum of its proper divisors (231511).

912821 is a wasteful number, since it uses less digits than its factorization.

912821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1460 (or 1453 counting only the distinct ones).

The product of its digits is 288, while the sum is 23.

The square root of 912821 is about 955.4166630324. The cubic root of 912821 is about 97.0052429235.

The spelling of 912821 in words is "nine hundred twelve thousand, eight hundred twenty-one".