1971077857091 has 16 divisors (see below), whose sum is σ = 2296267247808. Its totient is φ = 1656820838400.

The previous prime is 1971077857061. The next prime is 1971077857103. The reversal of 1971077857091 is 1907587701791.

It is not a de Polignac number, because 1971077857091 - 2⁶ = 1971077857027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1971077857061) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 504470 + ... + 2048571.

It is an arithmetic number, because the mean of its divisors is an integer number (143516702988).

Almost surely, 2^{1971077857091} is an apocalyptic number.

1971077857091 is a deficient number, since it is larger than the sum of its proper divisors (325189390717).

1971077857091 is a wasteful number, since it uses less digits than its factorization.

1971077857091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2555182.

The product of its (nonzero) digits is 7779240, while the sum is 62.

The spelling of 1971077857091 in words is "one trillion, nine hundred seventy-one billion, seventy-seven million, eight hundred fifty-seven thousand, ninety-one".