42197920 has 24 divisors (see below), whose sum is σ = 99692964. Its totient is φ = 16879104.

The previous prime is 42197891. The next prime is 42197951. The reversal of 42197920 is 2979124.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 35664784 + 6533136 = 5972^2 + 2556^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131709 + ... + 132028.

Almost surely, 2^42197920 is an apocalyptic number.

42197920 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42197920 is an abundant number, since it is smaller than the sum of its proper divisors (57495044).

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

42197920 is a wasteful number, since it uses less digits than its factorization.

42197920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263752 (or 263744 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 42197920 is about 6495.9926108332. The cubic root of 42197920 is about 348.1478211131.

Subtracting from 42197920 its reverse (2979124), we obtain a triangular number (39218796 = T₈₈₅₆).

The spelling of 42197920 in words is "forty-two million, one hundred ninety-seven thousand, nine hundred twenty".