2109857749477 has 8 divisors (see below), whose sum is σ = 2234064736152. Its totient is φ = 1985661619200.

The previous prime is 2109857749459. The next prime is 2109857749487. The reversal of 2109857749477 is 7749477589012.

It can be written as a sum of positive squares in 4 ways, for example, as 1364408550241 + 745449199236 = 1168079^2 + 863394^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2109857749477 - 2³⁹ = 1560101935589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2109857749487) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2312274 + ... + 3092947.

It is an arithmetic number, because the mean of its divisors is an integer number (279258092019).

Almost surely, 2^{2109857749477} is an apocalyptic number.

It is an amenable number.

2109857749477 is a deficient number, since it is larger than the sum of its proper divisors (124206986675).

2109857749477 is a wasteful number, since it uses less digits than its factorization.

2109857749477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5428199.

The product of its (nonzero) digits is 248935680, while the sum is 70.

The spelling of 2109857749477 in words is "two trillion, one hundred nine billion, eight hundred fifty-seven million, seven hundred forty-nine thousand, four hundred seventy-seven".