135415521100021 has 16 divisors (see below), whose sum is σ = 137105055345600. Its totient is φ = 133729740144000.

The previous prime is 135415521100001. The next prime is 135415521100039. The reversal of 135415521100021 is 120001125514531.

It is a cyclic number.

It is not a de Polignac number, because 135415521100021 - 2¹⁹ = 135415520575733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135415521100001) 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, 1475534866 + ... + 1475626636.

It is an arithmetic number, because the mean of its divisors is an integer number (8569065959100).

Almost surely, 2^{135415521100021} is an apocalyptic number.

It is an amenable number.

135415521100021 is a deficient number, since it is larger than the sum of its proper divisors (1689534245579).

135415521100021 is an equidigital number, since it uses as much as digits as its factorization.

135415521100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112020.

The product of its (nonzero) digits is 6000, while the sum is 31.

Adding to 135415521100021 its reverse (120001125514531), we get a palindrome (255416646614552).

The spelling of 135415521100021 in words is "one hundred thirty-five trillion, four hundred fifteen billion, five hundred twenty-one million, one hundred thousand, twenty-one".