209357493136 has 45 divisors (see below), whose sum is σ = 445900804923. Its totient is φ = 95153345760.

The previous prime is 209357493119. The next prime is 209357493197. The reversal of 209357493136 is 631394753902.

It is a happy number.

The square root of 209357493136 is 457556.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×209357493136² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 20127265 + ... + 20137663.

Almost surely, 2^209357493136 is an apocalyptic number.

209357493136 is the 457556-th square number.

It is an amenable number.

209357493136 is an abundant number, since it is smaller than the sum of its proper divisors (236543311787).

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

209357493136 is an frugal number, since it uses more digits than its factorization.

209357493136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20828 (or 10412 counting only the distinct ones).

The product of its (nonzero) digits is 3674160, while the sum is 52.

The spelling of 209357493136 in words is "two hundred nine billion, three hundred fifty-seven million, four hundred ninety-three thousand, one hundred thirty-six".