19997250 has 128 divisors (see below), whose sum is σ = 61641216. Its totient is φ = 4204800.

The previous prime is 19997227. The next prime is 19997251. The reversal of 19997250 is 5279991.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19997251) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 68104 + ... + 68396.

It is an arithmetic number, because the mean of its divisors is an integer number (481572).

Almost surely, 2^19997250 is an apocalyptic number.

19997250 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19997250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30820608).

19997250 is an abundant number, since it is smaller than the sum of its proper divisors (41643966).

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

19997250 is a wasteful number, since it uses less digits than its factorization.

19997250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 51030, while the sum is 42.

The square root of 19997250 is about 4471.8284850830. The cubic root of 19997250 is about 271.4293200085.

The spelling of 19997250 in words is "nineteen million, nine hundred ninety-seven thousand, two hundred fifty".