54191989 has 2 divisors, whose sum is σ = 54191990. Its totient is φ = 54191988.

The previous prime is 54191941. The next prime is 54191993. The reversal of 54191989 is 98919145.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30747025 + 23444964 = 5545^2 + 4842^2 .

It is a cyclic number.

It is not a de Polignac number, because 54191989 - 2⁷ = 54191861 is a prime.

It is a super-2 number, since 2×54191989² = 5873543343552242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (54191089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27095994 + 27095995.

It is an arithmetic number, because the mean of its divisors is an integer number (27095995).

Almost surely, 2^54191989 is an apocalyptic number.

It is an amenable number.

54191989 is a deficient number, since it is larger than the sum of its proper divisors (1).

54191989 is an equidigital number, since it uses as much as digits as its factorization.

54191989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 46.

The square root of 54191989 is about 7361.5208347189. The cubic root of 54191989 is about 378.4237314095.

The spelling of 54191989 in words is "fifty-four million, one hundred ninety-one thousand, nine hundred eighty-nine".