1238721 has 8 divisors (see below), whose sum is σ = 1801824. Its totient is φ = 750720.

The previous prime is 1238719. The next prime is 1238747. The reversal of 1238721 is 1278321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1238721 - 2¹ = 1238719 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 1238691 and 1238700.

It is not an unprimeable number, because it can be changed into a prime (1238761) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18736 + ... + 18801.

It is an arithmetic number, because the mean of its divisors is an integer number (225228).

2^1238721 is an apocalyptic number.

1238721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1238721 is a deficient number, since it is larger than the sum of its proper divisors (563103).

1238721 is a wasteful number, since it uses less digits than its factorization.

1238721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37551.

The product of its digits is 672, while the sum is 24.

The square root of 1238721 is about 1112.9784364488. The cubic root of 1238721 is about 107.3967568350.

The spelling of 1238721 in words is "one million, two hundred thirty-eight thousand, seven hundred twenty-one".