42123240 has 80 divisors (see below), whose sum is σ = 141591780. Its totient is φ = 11232000.

The previous prime is 42123239. The next prime is 42123259. The reversal of 42123240 is 4232124.

42123240 = T₁₄₉ + T₁₅₀ + ... + T₆₃₄.

42123240 is a `hidden beast` number, since 421 + 2 + 3 + 240 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 35497764 + 6625476 = 5958^2 + 2574^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3261 + ... + 9740.

Almost surely, 2^42123240 is an apocalyptic number.

42123240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42123240 is an abundant number, since it is smaller than the sum of its proper divisors (99468540).

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

42123240 is a wasteful number, since it uses less digits than its factorization.

42123240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13024 (or 13011 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 42123240 is about 6490.2419061234. The cubic root of 42123240 is about 347.9423209994.

Adding to 42123240 its reverse (4232124), we get a palindrome (46355364).

The spelling of 42123240 in words is "forty-two million, one hundred twenty-three thousand, two hundred forty".