242720640 has 96 divisors (see below), whose sum is σ = 838164600. Its totient is φ = 64723968.

The previous prime is 242720617. The next prime is 242720651. The reversal of 242720640 is 46027242.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15310 + ... + 26829.

Almost surely, 2^242720640 is an apocalyptic number.

242720640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

242720640 is an abundant number, since it is smaller than the sum of its proper divisors (595443960).

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

242720640 is a wasteful number, since it uses less digits than its factorization.

242720640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42164 (or 42149 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 27.

The square root of 242720640 is about 15579.4942151535. The cubic root of 242720640 is about 623.7859226195.

Adding to 242720640 its reverse (46027242), we get a palindrome (288747882).

The spelling of 242720640 in words is "two hundred forty-two million, seven hundred twenty thousand, six hundred forty".