1238506365561 has 32 divisors (see below), whose sum is σ = 1667212753920. Its totient is φ = 817771896000.

The previous prime is 1238506365521. The next prime is 1238506365587. The reversal of 1238506365561 is 1655636058321.

It is not a de Polignac number, because 1238506365561 - 2⁶ = 1238506365497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1238506365521) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 239137470 + ... + 239142648.

It is an arithmetic number, because the mean of its divisors is an integer number (52100398560).

Almost surely, 2^{1238506365561} is an apocalyptic number.

It is an amenable number.

1238506365561 is a deficient number, since it is larger than the sum of its proper divisors (428706388359).

1238506365561 is a wasteful number, since it uses less digits than its factorization.

1238506365561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6797.

The product of its (nonzero) digits is 3888000, while the sum is 51.

The spelling of 1238506365561 in words is "one trillion, two hundred thirty-eight billion, five hundred six million, three hundred sixty-five thousand, five hundred sixty-one".