50991971 has 4 divisors (see below), whose sum is σ = 51496944. Its totient is φ = 50487000.

The previous prime is 50991961. The next prime is 50991973. The reversal of 50991971 is 17919905.

It is a happy number.

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 50991971 - 2⁶ = 50991907 is a prime.

It is a super-2 number, since 2×50991971² = 5200362212929682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (50991973) 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 in 3 ways as a sum of consecutive naturals, for example, 252335 + ... + 252536.

It is an arithmetic number, because the mean of its divisors is an integer number (12874236).

Almost surely, 2^50991971 is an apocalyptic number.

50991971 is a deficient number, since it is larger than the sum of its proper divisors (504973).

50991971 is a wasteful number, since it uses less digits than its factorization.

50991971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504972.

The product of its (nonzero) digits is 25515, while the sum is 41.

The square root of 50991971 is about 7140.8662639767. The cubic root of 50991971 is about 370.8235151323.

The spelling of 50991971 in words is "fifty million, nine hundred ninety-one thousand, nine hundred seventy-one".