823779642 has 32 divisors (see below), whose sum is σ = 1993686912. Its totient is φ = 221520384.

The previous prime is 823779641. The next prime is 823779679. The reversal of 823779642 is 246977328.

It is a super-2 number, since 2×823779642² = 1357225797147296328, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 823779591 and 823779600.

It is not an unprimeable number, because it can be changed into a prime (823779641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 576163 + ... + 577590.

It is an arithmetic number, because the mean of its divisors is an integer number (62302716).

Almost surely, 2^823779642 is an apocalyptic number.

823779642 is an abundant number, since it is smaller than the sum of its proper divisors (1169907270).

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

823779642 is a wasteful number, since it uses less digits than its factorization.

823779642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1153782.

The product of its digits is 1016064, while the sum is 48.

The square root of 823779642 is about 28701.5616648293. The cubic root of 823779642 is about 937.4260509849.

The spelling of 823779642 in words is "eight hundred twenty-three million, seven hundred seventy-nine thousand, six hundred forty-two".