238942821 has 16 divisors (see below), whose sum is σ = 345723840. Its totient is φ = 145916160.

The previous prime is 238942819. The next prime is 238942829. The reversal of 238942821 is 128249832.

It is not a de Polignac number, because 238942821 - 2¹ = 238942819 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 238942821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (238942829) 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, 18276 + ... + 28493.

It is an arithmetic number, because the mean of its divisors is an integer number (21607740).

Almost surely, 2^238942821 is an apocalyptic number.

It is an amenable number.

238942821 is a deficient number, since it is larger than the sum of its proper divisors (106781019).

238942821 is a wasteful number, since it uses less digits than its factorization.

238942821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46916.

The product of its digits is 55296, while the sum is 39.

The square root of 238942821 is about 15457.7754220975. The cubic root of 238942821 is about 620.5326856282.

The spelling of 238942821 in words is "two hundred thirty-eight million, nine hundred forty-two thousand, eight hundred twenty-one".