1221400202305 has 4 divisors (see below), whose sum is σ = 1465680242772. Its totient is φ = 977120161840.

The previous prime is 1221400202263. The next prime is 1221400202371. The reversal of 1221400202305 is 5032020041221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 813806060544 + 407594141761 = 902112^2 + 638431^2 .

It is not a de Polignac number, because 1221400202305 - 2³⁹ = 671644388417 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122140020226 + ... + 122140020235.

It is an arithmetic number, because the mean of its divisors is an integer number (366420060693).

Almost surely, 2^{1221400202305} is an apocalyptic number.

It is an amenable number.

1221400202305 is a deficient number, since it is larger than the sum of its proper divisors (244280040467).

1221400202305 is an equidigital number, since it uses as much as digits as its factorization.

1221400202305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244280040466.

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 1221400202305 its reverse (5032020041221), we get a palindrome (6253420243526).

The spelling of 1221400202305 in words is "one trillion, two hundred twenty-one billion, four hundred million, two hundred two thousand, three hundred five".