49981891 has 4 divisors (see below), whose sum is σ = 50218984. Its totient is φ = 49744800.

The previous prime is 49981879. The next prime is 49981907. The reversal of 49981891 is 19818994.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 49981891 - 2²⁵ = 16427459 is a prime.

It is a super-3 number, since 3×49981891³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (49981801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118230 + ... + 118651.

It is an arithmetic number, because the mean of its divisors is an integer number (12554746).

Almost surely, 2^49981891 is an apocalyptic number.

49981891 is a deficient number, since it is larger than the sum of its proper divisors (237093).

49981891 is a wasteful number, since it uses less digits than its factorization.

49981891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237092.

The product of its digits is 186624, while the sum is 49.

The square root of 49981891 is about 7069.7871962316. The cubic root of 49981891 is about 368.3586684092.

It can be divided in two parts, 4998 and 1891, that added together give a square (6889 = 83²).

The spelling of 49981891 in words is "forty-nine million, nine hundred eighty-one thousand, eight hundred ninety-one".