90721547 has 8 divisors (see below), whose sum is σ = 104428800. Its totient is φ = 77201064.

The previous prime is 90721511. The next prime is 90721549. The reversal of 90721547 is 74512709.

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 90721547 - 2¹⁸ = 90459403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90721549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45647 + ... + 47592.

It is an arithmetic number, because the mean of its divisors is an integer number (13053600).

Almost surely, 2^90721547 is an apocalyptic number.

90721547 is a deficient number, since it is larger than the sum of its proper divisors (13707253).

90721547 is a wasteful number, since it uses less digits than its factorization.

90721547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93385.

The product of its (nonzero) digits is 17640, while the sum is 35.

The square root of 90721547 is about 9524.7859293530. The cubic root of 90721547 is about 449.3348972939.

The spelling of 90721547 in words is "ninety million, seven hundred twenty-one thousand, five hundred forty-seven".