4215131991 has 48 divisors (see below), whose sum is σ = 7225108800. Its totient is φ = 2316916224.

The previous prime is 4215131983. The next prime is 4215132001. The reversal of 4215131991 is 1991315124.

4215131991 is a `hidden beast` number, since 42 + 1 + 513 + 19 + 91 = 666.

4215131991 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 4215131991 - 2³ = 4215131983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4215111991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 501915 + ... + 510243.

It is an arithmetic number, because the mean of its divisors is an integer number (150523100).

Almost surely, 2^4215131991 is an apocalyptic number.

4215131991 is a deficient number, since it is larger than the sum of its proper divisors (3009976809).

4215131991 is a wasteful number, since it uses less digits than its factorization.

4215131991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8648 (or 8645 counting only the distinct ones).

The product of its digits is 9720, while the sum is 36.

The square root of 4215131991 is about 64924.0478636383. The cubic root of 4215131991 is about 1615.3639734688.

The spelling of 4215131991 in words is "four billion, two hundred fifteen million, one hundred thirty-one thousand, nine hundred ninety-one".