1221215020447 has 2 divisors, whose sum is σ = 1221215020448. Its totient is φ = 1221215020446.

The previous prime is 1221215020433. The next prime is 1221215020457. The reversal of 1221215020447 is 7440205121221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221215020447 - 2¹¹ = 1221215018399 is a prime.

It is a super-2 number, since 2×1221215020447² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221215020457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610607510223 + 610607510224.

It is an arithmetic number, because the mean of its divisors is an integer number (610607510224).

Almost surely, 2^{1221215020447} is an apocalyptic number.

1221215020447 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221215020447 is an equidigital number, since it uses as much as digits as its factorization.

1221215020447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8960, while the sum is 31.

The spelling of 1221215020447 in words is "one trillion, two hundred twenty-one billion, two hundred fifteen million, twenty thousand, four hundred forty-seven".