1227401721 has 64 divisors (see below), whose sum is σ = 2276198400. Its totient is φ = 636372288.

The previous prime is 1227401689. The next prime is 1227401723. The reversal of 1227401721 is 1271047221.

It is a happy number.

It is not a de Polignac number, because 1227401721 - 2⁵ = 1227401689 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1227401723) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 140730 + ... + 149196.

It is an arithmetic number, because the mean of its divisors is an integer number (35565600).

Almost surely, 2^1227401721 is an apocalyptic number.

It is an amenable number.

1227401721 is a deficient number, since it is larger than the sum of its proper divisors (1048796679).

1227401721 is a wasteful number, since it uses less digits than its factorization.

1227401721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8555 (or 8549 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 27.

The square root of 1227401721 is about 35034.2934993700. The cubic root of 1227401721 is about 1070.6862924783.

Adding to 1227401721 its reverse (1271047221), we get a palindrome (2498448942).

The spelling of 1227401721 in words is "one billion, two hundred twenty-seven million, four hundred one thousand, seven hundred twenty-one".