47321891 has 2 divisors, whose sum is σ = 47321892. Its totient is φ = 47321890.

The previous prime is 47321873. The next prime is 47321921. The reversal of 47321891 is 19812374.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-47321891 is a prime.

It is a super-2 number, since 2×47321891² = 4478722735631762, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (47321821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23660945 + 23660946.

It is an arithmetic number, because the mean of its divisors is an integer number (23660946).

Almost surely, 2^47321891 is an apocalyptic number.

47321891 is a deficient number, since it is larger than the sum of its proper divisors (1).

47321891 is an equidigital number, since it uses as much as digits as its factorization.

47321891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 35.

The square root of 47321891 is about 6879.0908556291. The cubic root of 47321891 is about 361.7045986062.

Subtracting from 47321891 its sum of digits (35), we obtain a triangular number (47321856 = T₉₇₂₈).

The spelling of 47321891 in words is "forty-seven million, three hundred twenty-one thousand, eight hundred ninety-one".