209120021902 has 16 divisors (see below), whose sum is σ = 353996276400. Its totient is φ = 91776811840.

The previous prime is 209120021893. The next prime is 209120021921.

209120021902 is nontrivially palindromic in base 10.

It is a congruent 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, 163886527 + ... + 163887802.

It is an arithmetic number, because the mean of its divisors is an integer number (22124767275).

Almost surely, 2^209120021902 is an apocalyptic number.

209120021902 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

209120021902 is a deficient number, since it is larger than the sum of its proper divisors (144876254498).

209120021902 is a wasteful number, since it uses less digits than its factorization.

209120021902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327774371.

The product of its (nonzero) digits is 1296, while the sum is 28.

The spelling of 209120021902 in words is "two hundred nine billion, one hundred twenty million, twenty-one thousand, nine hundred two".