2171942892737 has 4 divisors (see below), whose sum is σ = 2171947193796. Its totient is φ = 2171938591680.

The previous prime is 2171942892661. The next prime is 2171942892797. The reversal of 2171942892737 is 7372982491712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 231942412816 + 1940000479921 = 481604^2 + 1392839^2 .

It is a cyclic number.

It is not a de Polignac number, because 2171942892737 - 2¹² = 2171942888641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2171942892737.

It is not an unprimeable number, because it can be changed into a prime (2171942892797) 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, 1273964 + ... + 2442717.

It is an arithmetic number, because the mean of its divisors is an integer number (542986798449).

Almost surely, 2^{2171942892737} is an apocalyptic number.

It is an amenable number.

2171942892737 is a deficient number, since it is larger than the sum of its proper divisors (4301059).

2171942892737 is an equidigital number, since it uses as much as digits as its factorization.

2171942892737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4301058.

The product of its digits is 21337344, while the sum is 62.

The spelling of 2171942892737 in words is "two trillion, one hundred seventy-one billion, nine hundred forty-two million, eight hundred ninety-two thousand, seven hundred thirty-seven".