16209972 has 18 divisors (see below), whose sum is σ = 40975298. Its totient is φ = 5403312.

The previous prime is 16209967. The next prime is 16210013. The reversal of 16209972 is 27990261.

It can be written as a sum of positive squares in only one way, i.e., 16208676 + 1296 = 4026^2 + 36^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 450277 = 16209972 / (1 + 6 + 2 + 0 + 9 + 9 + 7 + 2).

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 225103 + ... + 225174.

Almost surely, 2^16209972 is an apocalyptic number.

16209972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

16209972 is an abundant number, since it is smaller than the sum of its proper divisors (24765326).

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

16209972 is a wasteful number, since it uses less digits than its factorization.

16209972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450287 (or 450282 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 16209972 is about 4026.1609505831. The cubic root of 16209972 is about 253.0817069077.

The spelling of 16209972 in words is "sixteen million, two hundred nine thousand, nine hundred seventy-two".