823772421 has 12 divisors (see below), whose sum is σ = 1204956480. Its totient is φ = 542229480.

The previous prime is 823772413. The next prime is 823772471. The reversal of 823772421 is 124277328.

It is not a de Polignac number, because 823772421 - 2³ = 823772413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (823772401) 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, 578595 + ... + 580016.

It is an arithmetic number, because the mean of its divisors is an integer number (100413040).

Almost surely, 2^823772421 is an apocalyptic number.

It is an amenable number.

823772421 is a deficient number, since it is larger than the sum of its proper divisors (381184059).

823772421 is a wasteful number, since it uses less digits than its factorization.

823772421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1158696 (or 1158693 counting only the distinct ones).

The product of its digits is 37632, while the sum is 36.

The square root of 823772421 is about 28701.4358700048. The cubic root of 823772421 is about 937.4233119137.

The spelling of 823772421 in words is "eight hundred twenty-three million, seven hundred seventy-two thousand, four hundred twenty-one".