1970801891 has 4 divisors (see below), whose sum is σ = 2086731432. Its totient is φ = 1854872352.

The previous prime is 1970801879. The next prime is 1970801893. The reversal of 1970801891 is 1981080791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1981080791 = 7723 ⋅256517.

It is a cyclic number.

It is not a de Polignac number, because 1970801891 - 2³⁰ = 897060067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1970801893) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57964745 + ... + 57964778.

It is an arithmetic number, because the mean of its divisors is an integer number (521682858).

Almost surely, 2^1970801891 is an apocalyptic number.

1970801891 is a deficient number, since it is larger than the sum of its proper divisors (115929541).

1970801891 is a wasteful number, since it uses less digits than its factorization.

1970801891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115929540.

The product of its (nonzero) digits is 36288, while the sum is 44.

The square root of 1970801891 is about 44393.7145438406. The cubic root of 1970801891 is about 1253.7597501650.

The spelling of 1970801891 in words is "one billion, nine hundred seventy million, eight hundred one thousand, eight hundred ninety-one".