121221534501 has 16 divisors (see below), whose sum is σ = 179634611520. Its totient is φ = 80793137520.

The previous prime is 121221534487. The next prime is 121221534521. The reversal of 121221534501 is 105435122121.

It is a happy number.

121221534501 is a `hidden beast` number, since 1 + 2 + 1 + 2 + 2 + 153 + 4 + 501 = 666.

It is not a de Polignac number, because 121221534501 - 2⁷ = 121221534373 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221534521) 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, 484335 + ... + 690668.

It is an arithmetic number, because the mean of its divisors is an integer number (11227163220).

Almost surely, 2^121221534501 is an apocalyptic number.

It is an amenable number.

121221534501 is a deficient number, since it is larger than the sum of its proper divisors (58413077019).

121221534501 is a wasteful number, since it uses less digits than its factorization.

121221534501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178833 (or 1178827 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 121221534501 its reverse (105435122121), we get a palindrome (226656656622).

The spelling of 121221534501 in words is "one hundred twenty-one billion, two hundred twenty-one million, five hundred thirty-four thousand, five hundred one".