42071991 has 64 divisors (see below), whose sum is σ = 69672960. Its totient is φ = 22302720.

The previous prime is 42071977. The next prime is 42071993. The reversal of 42071991 is 19917024.

It is not a de Polignac number, because 42071991 - 2⁵ = 42071959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42071993) 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, 472675 + ... + 472763.

It is an arithmetic number, because the mean of its divisors is an integer number (1088640).

Almost surely, 2^42071991 is an apocalyptic number.

42071991 is a deficient number, since it is larger than the sum of its proper divisors (27600969).

42071991 is a wasteful number, since it uses less digits than its factorization.

42071991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 42071991 is about 6486.2925465939. The cubic root of 42071991 is about 347.8011563873.

The spelling of 42071991 in words is "forty-two million, seventy-one thousand, nine hundred ninety-one".