19921320 has 48 divisors (see below), whose sum is σ = 64745460. Its totient is φ = 5312256.

The previous prime is 19921303. The next prime is 19921327. The reversal of 19921320 is 2312991.

19921320 is nontrivially palindromic in base 11.

It can be written as a sum of positive squares in 2 ways, for example, as 19554084 + 367236 = 4422^2 + 606^2 .

It is not an unprimeable number, because it can be changed into a prime (19921327) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27309 + ... + 28028.

Almost surely, 2^19921320 is an apocalyptic number.

19921320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19921320 is an abundant number, since it is smaller than the sum of its proper divisors (44824140).

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

19921320 is a wasteful number, since it uses less digits than its factorization.

19921320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55354 (or 55347 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 19921320 is about 4463.3305949705. The cubic root of 19921320 is about 271.0853432366.

The spelling of 19921320 in words is "nineteen million, nine hundred twenty-one thousand, three hundred twenty".