121521400545 has 16 divisors (see below), whose sum is σ = 197729737920. Its totient is φ = 63712914624.

The previous prime is 121521400523. The next prime is 121521400621. The reversal of 121521400545 is 545004125121.

It is not a de Polignac number, because 121521400545 - 2⁵ = 121521400513 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68655274 + ... + 68657043.

It is an arithmetic number, because the mean of its divisors is an integer number (12358108620).

Almost surely, 2^121521400545 is an apocalyptic number.

121521400545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121521400545 is a deficient number, since it is larger than the sum of its proper divisors (76208337375).

121521400545 is a wasteful number, since it uses less digits than its factorization.

121521400545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137312384.

The product of its (nonzero) digits is 8000, while the sum is 30.

Adding to 121521400545 its reverse (545004125121), we get a palindrome (666525525666).

The spelling of 121521400545 in words is "one hundred twenty-one billion, five hundred twenty-one million, four hundred thousand, five hundred forty-five".