205742397786 has 16 divisors (see below), whose sum is σ = 411871905984. Its totient is φ = 68516280864.

The previous prime is 205742397761. The next prime is 205742397823. The reversal of 205742397786 is 687793247502.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16122691 + ... + 16135446.

It is an arithmetic number, because the mean of its divisors is an integer number (25741994124).

Almost surely, 2^205742397786 is an apocalyptic number.

205742397786 is an abundant number, since it is smaller than the sum of its proper divisors (206129508198).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

205742397786 is a wasteful number, since it uses less digits than its factorization.

205742397786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32259205.

The product of its (nonzero) digits is 35562240, while the sum is 60.

The spelling of 205742397786 in words is "two hundred five billion, seven hundred forty-two million, three hundred ninety-seven thousand, seven hundred eighty-six".