1200721 has 4 divisors (see below), whose sum is σ = 1216000. Its totient is φ = 1185444.

The previous prime is 1200701. The next prime is 1200739. The reversal of 1200721 is 1270021.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1270021 = 97 ⋅13093.

It is a cyclic number.

It is not a de Polignac number, because 1200721 - 2¹⁵ = 1167953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1200701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7521 + ... + 7678.

It is an arithmetic number, because the mean of its divisors is an integer number (304000).

2^1200721 is an apocalyptic number.

It is an amenable number.

1200721 is a deficient number, since it is larger than the sum of its proper divisors (15279).

1200721 is an equidigital number, since it uses as much as digits as its factorization.

1200721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15278.

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 1200721 is about 1095.7741555631. The cubic root of 1200721 is about 106.2871353469.

Adding to 1200721 its reverse (1270021), we get a palindrome (2470742).

The spelling of 1200721 in words is "one million, two hundred thousand, seven hundred twenty-one".