1221335153 has 2 divisors, whose sum is σ = 1221335154. Its totient is φ = 1221335152.

The previous prime is 1221335147. The next prime is 1221335173. The reversal of 1221335153 is 3515331221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1176284209 + 45050944 = 34297^2 + 6712^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221335153 - 2⁸ = 1221334897 is a prime.

It is a super-5 number, since 5×1221335153⁵ (a number of 47 digits) contains 55555 as substring.

It is not a weakly prime, because it can be changed into another prime (1221335173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610667576 + 610667577.

It is an arithmetic number, because the mean of its divisors is an integer number (610667577).

Almost surely, 2^1221335153 is an apocalyptic number.

It is an amenable number.

1221335153 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221335153 is an equidigital number, since it uses as much as digits as its factorization.

1221335153 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2700, while the sum is 26.

The square root of 1221335153 is about 34947.6058264368. The cubic root of 1221335153 is about 1068.9193833059.

Adding to 1221335153 its reverse (3515331221), we get a palindrome (4736666374).

The spelling of 1221335153 in words is "one billion, two hundred twenty-one million, three hundred thirty-five thousand, one hundred fifty-three".