19897215 has 48 divisors (see below), whose sum is σ = 35417088. Its totient is φ = 9529728.

The previous prime is 19897193. The next prime is 19897223. The reversal of 19897215 is 51279891.

19897215 = 353² + 354² + ... + 469².

It is not a de Polignac number, because 19897215 - 2⁵ = 19897183 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 119062 + ... + 119228.

It is an arithmetic number, because the mean of its divisors is an integer number (737856).

Almost surely, 2^19897215 is an apocalyptic number.

19897215 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

19897215 is a deficient number, since it is larger than the sum of its proper divisors (15519873).

19897215 is a wasteful number, since it uses less digits than its factorization.

19897215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248 (or 235 counting only the distinct ones).

The product of its digits is 45360, while the sum is 42.

The square root of 19897215 is about 4460.6294398885. The cubic root of 19897215 is about 270.9759604316.

The spelling of 19897215 in words is "nineteen million, eight hundred ninety-seven thousand, two hundred fifteen".