1221205232541 has 32 divisors (see below), whose sum is σ = 1911187345408. Its totient is φ = 679087644480.

The previous prime is 1221205232531. The next prime is 1221205232551. The reversal of 1221205232541 is 1452325021221.

It is an interprime number because it is at equal distance from previous prime (1221205232531) and next prime (1221205232551).

It is not a de Polignac number, because 1221205232541 - 2⁵ = 1221205232509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221205232499 and 1221205232508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221205232501) 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, 2250466 + ... + 2739891.

It is an arithmetic number, because the mean of its divisors is an integer number (59724604544).

Almost surely, 2^{1221205232541} is an apocalyptic number.

It is an amenable number.

1221205232541 is a deficient number, since it is larger than the sum of its proper divisors (689982112867).

1221205232541 is a wasteful number, since it uses less digits than its factorization.

1221205232541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4990681.

The product of its (nonzero) digits is 9600, while the sum is 30.

The spelling of 1221205232541 in words is "one trillion, two hundred twenty-one billion, two hundred five million, two hundred thirty-two thousand, five hundred forty-one".