918487521 has 24 divisors (see below), whose sum is σ = 1518445760. Its totient is φ = 524084256.

The previous prime is 918487517. The next prime is 918487547. The reversal of 918487521 is 125784819.

It is not a de Polignac number, because 918487521 - 2² = 918487517 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (918487511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34386 + ... + 54948.

Almost surely, 2^918487521 is an apocalyptic number.

It is an amenable number.

918487521 is a deficient number, since it is larger than the sum of its proper divisors (599958239).

918487521 is a wasteful number, since it uses less digits than its factorization.

918487521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21285 (or 21282 counting only the distinct ones).

The product of its digits is 161280, while the sum is 45.

The square root of 918487521 is about 30306.5590425571. The cubic root of 918487521 is about 972.0555555555.

The spelling of 918487521 in words is "nine hundred eighteen million, four hundred eighty-seven thousand, five hundred twenty-one".