1221961123 has 2 divisors, whose sum is σ = 1221961124. Its totient is φ = 1221961122.

The previous prime is 1221961099. The next prime is 1221961129. The reversal of 1221961123 is 3211691221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221961123 - 2²¹ = 1219863971 is a prime.

It is a super-2 number, since 2×1221961123² = 2986377972246842258, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221961091 and 1221961100.

It is not a weakly prime, because it can be changed into another prime (1221961129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610980561 + 610980562.

It is an arithmetic number, because the mean of its divisors is an integer number (610980562).

Almost surely, 2^1221961123 is an apocalyptic number.

1221961123 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221961123 is an equidigital number, since it uses as much as digits as its factorization.

1221961123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 28.

The square root of 1221961123 is about 34956.5605144442. The cubic root of 1221961123 is about 1069.1019696020.

The spelling of 1221961123 in words is "one billion, two hundred twenty-one million, nine hundred sixty-one thousand, one hundred twenty-three".