209213538 has 16 divisors (see below), whose sum is σ = 418686816. Its totient is φ = 69694560.

The previous prime is 209213519. The next prime is 209213539. The reversal of 209213538 is 835312902.

It is a junction number, because it is equal to n+sod(n) for n = 209213499 and 209213508.

It is not an unprimeable number, because it can be changed into a prime (209213539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 573 + ... + 20463.

It is an arithmetic number, because the mean of its divisors is an integer number (26167926).

Almost surely, 2^209213538 is an apocalyptic number.

209213538 is an abundant number, since it is smaller than the sum of its proper divisors (209473278).

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

209213538 is a wasteful number, since it uses less digits than its factorization.

209213538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21649.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 209213538 is about 14464.2157754923. The cubic root of 209213538 is about 593.6492561410.

The spelling of 209213538 in words is "two hundred nine million, two hundred thirteen thousand, five hundred thirty-eight".