1221929497 has 2 divisors, whose sum is σ = 1221929498. Its totient is φ = 1221929496.

The previous prime is 1221929483. The next prime is 1221929503. The reversal of 1221929497 is 7949291221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 891380736 + 330548761 = 29856^2 + 18181^2 .

It is an emirp because it is prime and its reverse (7949291221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221929497 - 2²⁷ = 1087711769 is a prime.

It is a super-2 number, since 2×1221929497² = 2986223391277346018, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1221924497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610964748 + 610964749.

It is an arithmetic number, because the mean of its divisors is an integer number (610964749).

Almost surely, 2^1221929497 is an apocalyptic number.

It is an amenable number.

1221929497 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221929497 is an equidigital number, since it uses as much as digits as its factorization.

1221929497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 46.

The square root of 1221929497 is about 34956.1081500787. The cubic root of 1221929497 is about 1069.0927462561.

The spelling of 1221929497 in words is "one billion, two hundred twenty-one million, nine hundred twenty-nine thousand, four hundred ninety-seven".