1221542155341 has 6 divisors (see below), whose sum is σ = 1764449779950. Its totient is φ = 814361436888.

The previous prime is 1221542155313. The next prime is 1221542155357. The reversal of 1221542155341 is 1435512451221.

1221542155341 is a `hidden beast` number, since 1 + 2 + 21 + 5 + 42 + 1 + 553 + 41 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1047357794025 + 174184361316 = 1023405^2 + 417354^2 .

It is not a de Polignac number, because 1221542155341 - 2¹³ = 1221542147149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221542155296 and 1221542155305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221542155541) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 67863453066 + ... + 67863453083.

It is an arithmetic number, because the mean of its divisors is an integer number (294074963325).

Almost surely, 2^{1221542155341} is an apocalyptic number.

It is an amenable number.

1221542155341 is a deficient number, since it is larger than the sum of its proper divisors (542907624609).

1221542155341 is a wasteful number, since it uses less digits than its factorization.

1221542155341 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135726906155 (or 135726906152 counting only the distinct ones).

The product of its digits is 48000, while the sum is 36.

The spelling of 1221542155341 in words is "one trillion, two hundred twenty-one billion, five hundred forty-two million, one hundred fifty-five thousand, three hundred forty-one".