1229801721 has 16 divisors (see below), whose sum is σ = 1664219520. Its totient is φ = 807645440.

The previous prime is 1229801719. The next prime is 1229801731. The reversal of 1229801721 is 1271089221.

It is a cyclic number.

It is not a de Polignac number, because 1229801721 - 2¹ = 1229801719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1229801701) 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, 470065 + ... + 472673.

It is an arithmetic number, because the mean of its divisors is an integer number (104013720).

Almost surely, 2^1229801721 is an apocalyptic number.

It is an amenable number.

1229801721 is a deficient number, since it is larger than the sum of its proper divisors (434417799).

1229801721 is a wasteful number, since it uses less digits than its factorization.

1229801721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4896.

The product of its (nonzero) digits is 4032, while the sum is 33.

The square root of 1229801721 is about 35068.5289255195. The cubic root of 1229801721 is about 1071.3836936149.

The spelling of 1229801721 in words is "one billion, two hundred twenty-nine million, eight hundred one thousand, seven hundred twenty-one".