209764020 has 48 divisors (see below), whose sum is σ = 621891648. Its totient is φ = 52646400.

The previous prime is 209764001. The next prime is 209764021. The reversal of 209764020 is 20467902.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209764021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 101806 + ... + 103845.

It is an arithmetic number, because the mean of its divisors is an integer number (12956076).

Almost surely, 2^209764020 is an apocalyptic number.

209764020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

209764020 is an abundant number, since it is smaller than the sum of its proper divisors (412127628).

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

209764020 is a wasteful number, since it uses less digits than its factorization.

209764020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205680 (or 205678 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 209764020 is about 14483.2323740248. The cubic root of 209764020 is about 594.1694694950.

The spelling of 209764020 in words is "two hundred nine million, seven hundred sixty-four thousand, twenty".