521870989 has 8 divisors (see below), whose sum is σ = 553792320. Its totient is φ = 490718976.

The previous prime is 521870971. The next prime is 521871023. The reversal of 521870989 is 989078125.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 521870989 - 2⁹ = 521870477 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521870969) 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 7 ways as a sum of consecutive naturals, for example, 190932 + ... + 193645.

It is an arithmetic number, because the mean of its divisors is an integer number (69224040).

Almost surely, 2^521870989 is an apocalyptic number.

521870989 is a gapful number since it is divisible by the number (59) formed by its first and last digit.

It is an amenable number.

521870989 is a deficient number, since it is larger than the sum of its proper divisors (31921331).

521870989 is a wasteful number, since it uses less digits than its factorization.

521870989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384659.

The product of its (nonzero) digits is 362880, while the sum is 49.

The square root of 521870989 is about 22844.4958140905. The cubic root of 521870989 is about 805.1084503400.

The spelling of 521870989 in words is "five hundred twenty-one million, eight hundred seventy thousand, nine hundred eighty-nine".