242991540 has 144 divisors (see below), whose sum is σ = 851497920. Its totient is φ = 55434240.

The previous prime is 242991533. The next prime is 242991571. The reversal of 242991540 is 45199242.

242991540 is a `hidden beast` number, since 2 + 4 + 29 + 91 + 540 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 242991495 and 242991504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 30051 + ... + 37269.

It is an arithmetic number, because the mean of its divisors is an integer number (5913180).

Almost surely, 2^242991540 is an apocalyptic number.

242991540 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 242991540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (425748960).

242991540 is an abundant number, since it is smaller than the sum of its proper divisors (608506380).

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

242991540 is a wasteful number, since it uses less digits than its factorization.

242991540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7262 (or 7257 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 242991540 is about 15588.1859111315. The cubic root of 242991540 is about 624.0179050582.

The spelling of 242991540 in words is "two hundred forty-two million, nine hundred ninety-one thousand, five hundred forty".