1221679949 has 16 divisors (see below), whose sum is σ = 1450080000. Its totient is φ = 1007385984.

The previous prime is 1221679933. The next prime is 1221679967. The reversal of 1221679949 is 9499761221.

It is a cyclic number.

It is not a de Polignac number, because 1221679949 - 2⁴ = 1221679933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221679897 and 1221679906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221679919) 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, 3449 + ... + 49550.

It is an arithmetic number, because the mean of its divisors is an integer number (90630000).

Almost surely, 2^1221679949 is an apocalyptic number.

It is an amenable number.

1221679949 is a deficient number, since it is larger than the sum of its proper divisors (228400051).

1221679949 is an equidigital number, since it uses as much as digits as its factorization.

1221679949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53132.

The product of its digits is 489888, while the sum is 50.

The square root of 1221679949 is about 34952.5385201132. The cubic root of 1221679949 is about 1069.0199629733.

The spelling of 1221679949 in words is "one billion, two hundred twenty-one million, six hundred seventy-nine thousand, nine hundred forty-nine".