1971358856 has 8 divisors (see below), whose sum is σ = 3696297870. Its totient is φ = 985679424.

The previous prime is 1971358841. The next prime is 1971358859. The reversal of 1971358856 is 6588531791.

It can be written as a sum of positive squares in only one way, i.e., 1837493956 + 133864900 = 42866^2 + 11570^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 1971358798 and 1971358807.

It is not an unprimeable number, because it can be changed into a prime (1971358859) 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 as a sum of consecutive naturals, namely, 123209921 + ... + 123209936.

Almost surely, 2^1971358856 is an apocalyptic number.

It is an amenable number.

1971358856 is a deficient number, since it is larger than the sum of its proper divisors (1724939014).

1971358856 is a wasteful number, since it uses less digits than its factorization.

1971358856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246419863 (or 246419859 counting only the distinct ones).

The product of its digits is 1814400, while the sum is 53.

The square root of 1971358856 is about 44399.9871171152. The cubic root of 1971358856 is about 1253.8778466838.

The spelling of 1971358856 in words is "one billion, nine hundred seventy-one million, three hundred fifty-eight thousand, eight hundred fifty-six".