42120440 has 32 divisors (see below), whose sum is σ = 95024880. Its totient is φ = 16803072.

The previous prime is 42120433. The next prime is 42120451. The reversal of 42120440 is 4402124.

42120440 = 1615² + 1616² + ... + 1630².

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16532 + ... + 18908.

Almost surely, 2^42120440 is an apocalyptic number.

42120440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42120440 is an abundant number, since it is smaller than the sum of its proper divisors (52904440).

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

42120440 is a wasteful number, since it uses less digits than its factorization.

42120440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2831 (or 2827 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 42120440 is about 6490.0261940920. The cubic root of 42120440 is about 347.9346113987.

Adding to 42120440 its reverse (4402124), we get a palindrome (46522564).

The spelling of 42120440 in words is "forty-two million, one hundred twenty thousand, four hundred forty".