1156061221555 has 16 divisors (see below), whose sum is σ = 1392438460320. Its totient is φ = 921406401792.

The previous prime is 1156061221501. The next prime is 1156061221559. The reversal of 1156061221555 is 5551221606511.

It is a cyclic number.

It is not a de Polignac number, because 1156061221555 - 2²¹ = 1156059124403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1156061221559) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13709632 + ... + 13793698.

It is an arithmetic number, because the mean of its divisors is an integer number (87027403770).

Almost surely, 2^{1156061221555} is an apocalyptic number.

1156061221555 is a deficient number, since it is larger than the sum of its proper divisors (236377238765).

1156061221555 is an equidigital number, since it uses as much as digits as its factorization.

1156061221555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94278.

The product of its (nonzero) digits is 90000, while the sum is 40.

The spelling of 1156061221555 in words is "one trillion, one hundred fifty-six billion, sixty-one million, two hundred twenty-one thousand, five hundred fifty-five".