42172540 has 12 divisors (see below), whose sum is σ = 88562376. Its totient is φ = 16869008.

The previous prime is 42172531. The next prime is 42172541. The reversal of 42172540 is 4527124.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42172541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1054294 + ... + 1054333.

It is an arithmetic number, because the mean of its divisors is an integer number (7380198).

Almost surely, 2^42172540 is an apocalyptic number.

It is an amenable number.

42172540 is an abundant number, since it is smaller than the sum of its proper divisors (46389836).

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

42172540 is a wasteful number, since it uses less digits than its factorization.

42172540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2108636 (or 2108634 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 25.

The square root of 42172540 is about 6494.0388049349. The cubic root of 42172540 is about 348.0780091116.

Adding to 42172540 its reverse (4527124), we get a palindrome (46699664).

The spelling of 42172540 in words is "forty-two million, one hundred seventy-two thousand, five hundred forty".