243791421 has 16 divisors (see below), whose sum is σ = 342491136. Its totient is φ = 153947376.

The previous prime is 243791419. The next prime is 243791423. The reversal of 243791421 is 124197342.

It is an interprime number because it is at equal distance from previous prime (243791419) and next prime (243791423).

It is not a de Polignac number, because 243791421 - 2¹ = 243791419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243791423) 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, 10045 + ... + 24258.

It is an arithmetic number, because the mean of its divisors is an integer number (21405696).

Almost surely, 2^243791421 is an apocalyptic number.

It is an amenable number.

243791421 is a deficient number, since it is larger than the sum of its proper divisors (98699715).

243791421 is a wasteful number, since it uses less digits than its factorization.

243791421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34432.

The product of its digits is 12096, while the sum is 33.

The square root of 243791421 is about 15613.8214732973. The cubic root of 243791421 is about 624.7018703993.

The spelling of 243791421 in words is "two hundred forty-three million, seven hundred ninety-one thousand, four hundred twenty-one".