1525135521 has 64 divisors (see below), whose sum is σ = 2554675200. Its totient is φ = 787988736.

The previous prime is 1525135519. The next prime is 1525135531. The reversal of 1525135521 is 1255315251.

It is not a de Polignac number, because 1525135521 - 2¹ = 1525135519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1525135531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3183760 + ... + 3184238.

It is an arithmetic number, because the mean of its divisors is an integer number (39916800).

Almost surely, 2^1525135521 is an apocalyptic number.

It is an amenable number.

1525135521 is a deficient number, since it is larger than the sum of its proper divisors (1029539679).

1525135521 is a wasteful number, since it uses less digits than its factorization.

1525135521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 718.

The product of its digits is 7500, while the sum is 30.

The square root of 1525135521 is about 39052.9835095861. The cubic root of 1525135521 is about 1151.0728541298.

The spelling of 1525135521 in words is "one billion, five hundred twenty-five million, one hundred thirty-five thousand, five hundred twenty-one".