16921290 has 32 divisors (see below), whose sum is σ = 43001280. Its totient is φ = 4246784.

The previous prime is 16921279. The next prime is 16921291. The reversal of 16921290 is 9212961.

It is a happy number.

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

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (16921291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16080 + ... + 17099.

It is an arithmetic number, because the mean of its divisors is an integer number (1343790).

Almost surely, 2^16921290 is an apocalyptic number.

16921290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16921290 is an abundant number, since it is smaller than the sum of its proper divisors (26079990).

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

16921290 is a wasteful number, since it uses less digits than its factorization.

16921290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33206.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 16921290 is about 4113.5495621179. The cubic root of 16921290 is about 256.7307105789.

The spelling of 16921290 in words is "sixteen million, nine hundred twenty-one thousand, two hundred ninety".