1221869507 has 2 divisors, whose sum is σ = 1221869508. Its totient is φ = 1221869506.

The previous prime is 1221869497. The next prime is 1221869513. The reversal of 1221869507 is 7059681221.

It is a strong prime.

It is an emirp because it is prime and its reverse (7059681221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221869507 - 2¹⁴ = 1221853123 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221869567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610934753 + 610934754.

It is an arithmetic number, because the mean of its divisors is an integer number (610934754).

Almost surely, 2^1221869507 is an apocalyptic number.

1221869507 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221869507 is an equidigital number, since it uses as much as digits as its factorization.

1221869507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60480, while the sum is 41.

The square root of 1221869507 is about 34955.2500634740. The cubic root of 1221869507 is about 1069.0752504503.

The spelling of 1221869507 in words is "one billion, two hundred twenty-one million, eight hundred sixty-nine thousand, five hundred seven".