521400042 has 24 divisors (see below), whose sum is σ = 1132158144. Its totient is φ = 173421864.

The previous prime is 521400037. The next prime is 521400053. The reversal of 521400042 is 240004125.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 521399988 and 521400024.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22948 + ... + 39615.

It is an arithmetic number, because the mean of its divisors is an integer number (47173256).

Almost surely, 2^521400042 is an apocalyptic number.

521400042 is an abundant number, since it is smaller than the sum of its proper divisors (610758102).

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

521400042 is a wasteful number, since it uses less digits than its factorization.

521400042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63034 (or 63031 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 521400042 is about 22834.1858186361. The cubic root of 521400042 is about 804.8661953706.

Adding to 521400042 its reverse (240004125), we get a palindrome (761404167).

The spelling of 521400042 in words is "five hundred twenty-one million, four hundred thousand, forty-two".