49991971 has 4 divisors (see below), whose sum is σ = 50083912. Its totient is φ = 49900032.

The previous prime is 49991927. The next prime is 49991993. The reversal of 49991971 is 17919994.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17919994 = 2 ⋅8959997.

It is a cyclic number.

It is not a de Polignac number, because 49991971 - 2¹⁹ = 49467683 is a prime.

It is the 7071-st Hogben number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (49991371) by changing a digit.

It is a nontrivial repunit in base 7070.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45150 + ... + 46243.

It is an arithmetic number, because the mean of its divisors is an integer number (12520978).

Almost surely, 2^49991971 is an apocalyptic number.

49991971 is a deficient number, since it is larger than the sum of its proper divisors (91941).

49991971 is an equidigital number, since it uses as much as digits as its factorization.

49991971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91940.

The product of its digits is 183708, while the sum is 49.

The square root of 49991971 is about 7070.5000530373. The cubic root of 49991971 is about 368.3834294158.

The spelling of 49991971 in words is "forty-nine million, nine hundred ninety-one thousand, nine hundred seventy-one".