42505780 has 24 divisors (see below), whose sum is σ = 94513608. Its totient is φ = 16002048.

The previous prime is 42505759. The next prime is 42505781. The reversal of 42505780 is 8750524.

It can be written as a sum of positive squares in 4 ways, for example, as 1468944 + 41036836 = 1212^2 + 6406^2 .

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42505781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62169 + ... + 62848.

It is an arithmetic number, because the mean of its divisors is an integer number (3938067).

Almost surely, 2^42505780 is an apocalyptic number.

It is an amenable number.

42505780 is an abundant number, since it is smaller than the sum of its proper divisors (52007828).

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

42505780 is a wasteful number, since it uses less digits than its factorization.

42505780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125043 (or 125041 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 42505780 is about 6519.6456958948. The cubic root of 42505780 is about 348.9924219010.

The spelling of 42505780 in words is "forty-two million, five hundred five thousand, seven hundred eighty".