55381491 has 24 divisors (see below), whose sum is σ = 88508160. Its totient is φ = 33087600.

The previous prime is 55381477. The next prime is 55381517. The reversal of 55381491 is 19418355.

55381491 is a `hidden beast` number, since 553 + 8 + 14 + 91 = 666.

It is not a de Polignac number, because 55381491 - 2⁹ = 55380979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55381411) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3090 + ... + 10968.

It is an arithmetic number, because the mean of its divisors is an integer number (3687840).

Almost surely, 2^55381491 is an apocalyptic number.

55381491 is a deficient number, since it is larger than the sum of its proper divisors (33126669).

55381491 is a wasteful number, since it uses less digits than its factorization.

55381491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7967 (or 7964 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 55381491 is about 7441.8741591080. The cubic root of 55381491 is about 381.1724889097.

The spelling of 55381491 in words is "fifty-five million, three hundred eighty-one thousand, four hundred ninety-one".