243019661640 has 64 divisors (see below), whose sum is σ = 833210271360. Its totient is φ = 55547351040.

The previous prime is 243019661627. The next prime is 243019661663. The reversal of 243019661640 is 46166910342.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 243019661592 and 243019661601.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144653721 + ... + 144655400.

It is an arithmetic number, because the mean of its divisors is an integer number (13018910490).

Almost surely, 2^243019661640 is an apocalyptic number.

243019661640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

243019661640 is an abundant number, since it is smaller than the sum of its proper divisors (590190609720).

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

243019661640 is a wasteful number, since it uses less digits than its factorization.

243019661640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 289309142 (or 289309138 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 42.

The spelling of 243019661640 in words is "two hundred forty-three billion, nineteen million, six hundred sixty-one thousand, six hundred forty".