1971647937 has 18 divisors (see below), whose sum is σ = 3312905778. Its totient is φ = 1126655712.

The previous prime is 1971647903. The next prime is 1971647959. The reversal of 1971647937 is 7397461791.

It can be written as a sum of positive squares in only one way, i.e., 1887815601 + 83832336 = 43449^2 + 9156^2 .

It is not a de Polignac number, because 1971647937 - 2⁷ = 1971647809 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1971645937) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2234988 + ... + 2235869.

It is an arithmetic number, because the mean of its divisors is an integer number (184050321).

Almost surely, 2^1971647937 is an apocalyptic number.

It is an amenable number.

1971647937 is a deficient number, since it is larger than the sum of its proper divisors (1341257841).

1971647937 is a wasteful number, since it uses less digits than its factorization.

1971647937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4470877 (or 4470867 counting only the distinct ones).

The product of its digits is 2000376, while the sum is 54.

The square root of 1971647937 is about 44403.2424153912. The cubic root of 1971647937 is about 1253.9391334361.

The spelling of 1971647937 in words is "one billion, nine hundred seventy-one million, six hundred forty-seven thousand, nine hundred thirty-seven".