242921640 has 64 divisors (see below), whose sum is σ = 784828800. Its totient is φ = 59795712.

The previous prime is 242921633. The next prime is 242921647. The reversal of 242921640 is 46129242.

242921640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (242921633) and next prime (242921647).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 242921598 and 242921607.

It is not an unprimeable number, because it can be changed into a prime (242921647) 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, 76300 + ... + 79419.

It is an arithmetic number, because the mean of its divisors is an integer number (12262950).

Almost surely, 2^242921640 is an apocalyptic number.

242921640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

242921640 is an abundant number, since it is smaller than the sum of its proper divisors (541907160).

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

242921640 is a wasteful number, since it uses less digits than its factorization.

242921640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155746 (or 155742 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 242921640 is about 15585.9436672920. The cubic root of 242921640 is about 623.9580634210.

The spelling of 242921640 in words is "two hundred forty-two million, nine hundred twenty-one thousand, six hundred forty".