242581840 has 80 divisors (see below), whose sum is σ = 603122112. Its totient is φ = 90417152.

The previous prime is 242581813. The next prime is 242581841. The reversal of 242581840 is 48185242.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a junction number, because it is equal to n+sod(n) for n = 242581796 and 242581805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242581841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144687 + ... + 146353.

Almost surely, 2^242581840 is an apocalyptic number.

242581840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 242581840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (301561056).

242581840 is an abundant number, since it is smaller than the sum of its proper divisors (360540272).

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

242581840 is a wasteful number, since it uses less digits than its factorization.

242581840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1804 (or 1798 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 34.

The square root of 242581840 is about 15575.0390047666. The cubic root of 242581840 is about 623.6669957808. Note that the first 3 decimals are identical.

The spelling of 242581840 in words is "two hundred forty-two million, five hundred eighty-one thousand, eight hundred forty".