47820091 has 4 divisors (see below), whose sum is σ = 52167384. Its totient is φ = 43472800.

The previous prime is 47820089. The next prime is 47820107. The reversal of 47820091 is 19002874.

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

It is a cyclic number.

It is not a de Polignac number, because 47820091 - 2¹ = 47820089 is a prime.

It is a super-2 number, since 2×47820091² = 4573522206496562, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (47820061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2173630 + ... + 2173651.

It is an arithmetic number, because the mean of its divisors is an integer number (13041846).

Almost surely, 2^47820091 is an apocalyptic number.

47820091 is a deficient number, since it is larger than the sum of its proper divisors (4347293).

47820091 is a wasteful number, since it uses less digits than its factorization.

47820091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4347292.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 47820091 is about 6915.2072275529. The cubic root of 47820091 is about 362.9694996217.

The spelling of 47820091 in words is "forty-seven million, eight hundred twenty thousand, ninety-one".