823127921 has 48 divisors (see below), whose sum is σ = 1073803392. Its totient is φ = 623750400.

The previous prime is 823127891. The next prime is 823127927. The reversal of 823127921 is 129721328.

It is not a de Polignac number, because 823127921 - 2¹⁰ = 823126897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (823127927) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5242775 + ... + 5242931.

It is an arithmetic number, because the mean of its divisors is an integer number (22370904).

Almost surely, 2^823127921 is an apocalyptic number.

It is an amenable number.

823127921 is a deficient number, since it is larger than the sum of its proper divisors (250675471).

823127921 is a wasteful number, since it uses less digits than its factorization.

823127921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390 (or 383 counting only the distinct ones).

The product of its digits is 12096, while the sum is 35.

The square root of 823127921 is about 28690.2060118083. The cubic root of 823127921 is about 937.1787755425.

The spelling of 823127921 in words is "eight hundred twenty-three million, one hundred twenty-seven thousand, nine hundred twenty-one".