19902240 has 192 divisors, whose sum is σ = 74027520. Its totient is φ = 4976640.

The previous prime is 19902221. The next prime is 19902241. The reversal of 19902240 is 4220991.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19902241) 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 31 ways as a sum of consecutive naturals, for example, 73305 + ... + 73575.

It is an arithmetic number, because the mean of its divisors is an integer number (385560).

Almost surely, 2^19902240 is an apocalyptic number.

19902240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19902240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37013760).

19902240 is an abundant number, since it is smaller than the sum of its proper divisors (54125280).

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

19902240 is a wasteful number, since it uses less digits than its factorization.

19902240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312 (or 298 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 19902240 is about 4461.1926656445. The cubic root of 19902240 is about 270.9987699821.

The spelling of 19902240 in words is "nineteen million, nine hundred two thousand, two hundred forty".