42818391 has 72 divisors (see below), whose sum is σ = 80170272. Its totient is φ = 21542400.

The previous prime is 42818371. The next prime is 42818407. The reversal of 42818391 is 19381824.

It is not a de Polignac number, because 42818391 - 2⁶ = 42818327 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42818371) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 312475 + ... + 312611.

It is an arithmetic number, because the mean of its divisors is an integer number (1113476).

Almost surely, 2^42818391 is an apocalyptic number.

42818391 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

42818391 is a deficient number, since it is larger than the sum of its proper divisors (37351881).

42818391 is a wasteful number, since it uses less digits than its factorization.

42818391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 199 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 42818391 is about 6543.5763157466. The cubic root of 42818391 is about 349.8458940615.

The spelling of 42818391 in words is "forty-two million, eight hundred eighteen thousand, three hundred ninety-one".