209000021155 has 8 divisors (see below), whose sum is σ = 254911501584. Its totient is φ = 164459032800.

The previous prime is 209000021141. The next prime is 209000021171. The reversal of 209000021155 is 551120000902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 209000021155 - 2⁵ = 209000021123 is a prime.

It is a Duffinian 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, 342622681 + ... + 342623290.

It is an arithmetic number, because the mean of its divisors is an integer number (31863937698).

Almost surely, 2^209000021155 is an apocalyptic number.

209000021155 is a deficient number, since it is larger than the sum of its proper divisors (45911480429).

209000021155 is an equidigital number, since it uses as much as digits as its factorization.

209000021155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685246037.

The product of its (nonzero) digits is 900, while the sum is 25.

The spelling of 209000021155 in words is "two hundred nine billion, twenty-one thousand, one hundred fifty-five".