209400957077 has 4 divisors (see below), whose sum is σ = 225508723020. Its totient is φ = 193293191136.

The previous prime is 209400957061. The next prime is 209400957079. The reversal of 209400957077 is 770759004902.

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 70891192516 + 138509764561 = 266254^2 + 372169^2 .

It is a cyclic number.

It is not a de Polignac number, because 209400957077 - 2⁴ = 209400957061 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 (209400957079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8053882952 + ... + 8053882977.

It is an arithmetic number, because the mean of its divisors is an integer number (56377180755).

Almost surely, 2^209400957077 is an apocalyptic number.

It is an amenable number.

209400957077 is a deficient number, since it is larger than the sum of its proper divisors (16107765943).

209400957077 is a wasteful number, since it uses less digits than its factorization.

209400957077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16107765942.

The product of its (nonzero) digits is 1111320, while the sum is 50.

The spelling of 209400957077 in words is "two hundred nine billion, four hundred million, nine hundred fifty-seven thousand, seventy-seven".