191720481 has 8 divisors (see below), whose sum is σ = 255752160. Its totient is φ = 127751232.

The previous prime is 191720471. The next prime is 191720483. The reversal of 191720481 is 184027191.

191720481 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 191720481 - 2¹⁰ = 191719457 is a prime.

It is a super-2 number, since 2×191720481² = 73513485669742722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (191720483) 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, 7896 + ... + 21113.

It is an arithmetic number, because the mean of its divisors is an integer number (31969020).

Almost surely, 2^191720481 is an apocalyptic number.

It is an amenable number.

191720481 is a deficient number, since it is larger than the sum of its proper divisors (64031679).

191720481 is a wasteful number, since it uses less digits than its factorization.

191720481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31215.

The product of its (nonzero) digits is 4032, while the sum is 33.

The square root of 191720481 is about 13846.3165137881. The cubic root of 191720481 is about 576.6197364922.

The spelling of 191720481 in words is "one hundred ninety-one million, seven hundred twenty thousand, four hundred eighty-one".