16205631257 has 4 divisors (see below), whose sum is σ = 16209815076. Its totient is φ = 16201447440.

The previous prime is 16205631251. The next prime is 16205631271. The reversal of 16205631257 is 75213650261.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75213650261 = 23 ⋅3270158707.

It can be written as a sum of positive squares in 2 ways, for example, as 9620471056 + 6585160201 = 98084^2 + 81149^2 .

It is a cyclic number.

It is not a de Polignac number, because 16205631257 - 2¹⁶ = 16205565721 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 16205631257.

It is not an unprimeable number, because it can be changed into a prime (16205631251) 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, 2086094 + ... + 2093847.

It is an arithmetic number, because the mean of its divisors is an integer number (4052453769).

Almost surely, 2^16205631257 is an apocalyptic number.

It is an amenable number.

16205631257 is a deficient number, since it is larger than the sum of its proper divisors (4183819).

16205631257 is an equidigital number, since it uses as much as digits as its factorization.

16205631257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4183818.

The product of its (nonzero) digits is 75600, while the sum is 38.

The spelling of 16205631257 in words is "sixteen billion, two hundred five million, six hundred thirty-one thousand, two hundred fifty-seven".