209438190455 has 16 divisors (see below), whose sum is σ = 273699699840. Its totient is φ = 152924268288.

The previous prime is 209438190439. The next prime is 209438190497. The reversal of 209438190455 is 554091834902.

It is a cyclic number.

It is not a de Polignac number, because 209438190455 - 2⁴ = 209438190439 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18096047 + ... + 18107616.

It is an arithmetic number, because the mean of its divisors is an integer number (17106231240).

Almost surely, 2^209438190455 is an apocalyptic number.

209438190455 is a deficient number, since it is larger than the sum of its proper divisors (64261509385).

209438190455 is a wasteful number, since it uses less digits than its factorization.

209438190455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36203770.

The product of its (nonzero) digits is 1555200, while the sum is 50.

The spelling of 209438190455 in words is "two hundred nine billion, four hundred thirty-eight million, one hundred ninety thousand, four hundred fifty-five".