521542145 has 4 divisors (see below), whose sum is σ = 625850580. Its totient is φ = 417233712.

The previous prime is 521542111. The next prime is 521542157. The reversal of 521542145 is 541245125.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 127757809 + 393784336 = 11303^2 + 19844^2 .

It is a cyclic number.

It is not a de Polignac number, because 521542145 - 2⁶ = 521542081 is a prime.

It is a super-2 number, since 2×521542145² = 544012418022402050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52154210 + ... + 52154219.

It is an arithmetic number, because the mean of its divisors is an integer number (156462645).

Almost surely, 2^521542145 is an apocalyptic number.

It is an amenable number.

521542145 is a deficient number, since it is larger than the sum of its proper divisors (104308435).

521542145 is a wasteful number, since it uses less digits than its factorization.

521542145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104308434.

The product of its digits is 8000, while the sum is 29.

The square root of 521542145 is about 22837.2972350057. The cubic root of 521542145 is about 804.9393084653.

The spelling of 521542145 in words is "five hundred twenty-one million, five hundred forty-two thousand, one hundred forty-five".