820542392 has 8 divisors (see below), whose sum is σ = 1538517000. Its totient is φ = 410271192.

The previous prime is 820542347. The next prime is 820542397. The reversal of 820542392 is 293245028.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820542397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51283892 + ... + 51283907.

It is an arithmetic number, because the mean of its divisors is an integer number (192314625).

Almost surely, 2^820542392 is an apocalyptic number.

It is an amenable number.

820542392 is a deficient number, since it is larger than the sum of its proper divisors (717974608).

820542392 is a wasteful number, since it uses less digits than its factorization.

820542392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102567805 (or 102567801 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 820542392 is about 28645.1111361084. Note that the first 4 decimals coincide. The cubic root of 820542392 is about 936.1964882015.

The spelling of 820542392 in words is "eight hundred twenty million, five hundred forty-two thousand, three hundred ninety-two".