1310028721 has 16 divisors (see below), whose sum is σ = 1436617728. Its totient is φ = 1189209600.

The previous prime is 1310028703. The next prime is 1310028767. The reversal of 1310028721 is 1278200131.

It is a happy number.

It is not a de Polignac number, because 1310028721 - 2¹⁷ = 1309897649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1310028121) 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, 159901 + ... + 167893.

It is an arithmetic number, because the mean of its divisors is an integer number (89788608).

Almost surely, 2^1310028721 is an apocalyptic number.

It is an amenable number.

1310028721 is a deficient number, since it is larger than the sum of its proper divisors (126589007).

1310028721 is a wasteful number, since it uses less digits than its factorization.

1310028721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8352.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 1310028721 is about 36194.3189050436. The cubic root of 1310028721 is about 1094.1921777590.

Adding to 1310028721 its reverse (1278200131), we get a palindrome (2588228852).

The spelling of 1310028721 in words is "one billion, three hundred ten million, twenty-eight thousand, seven hundred twenty-one".