215332542121 has 4 divisors (see below), whose sum is σ = 215351424144. Its totient is φ = 215313660100.

The previous prime is 215332542101. The next prime is 215332542137. The reversal of 215332542121 is 121245233512.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 215332542121 - 2⁷ = 215332541993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215332542101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9423895 + ... + 9446716.

It is an arithmetic number, because the mean of its divisors is an integer number (53837856036).

Almost surely, 2^215332542121 is an apocalyptic number.

It is an amenable number.

215332542121 is a deficient number, since it is larger than the sum of its proper divisors (18882023).

215332542121 is a wasteful number, since it uses less digits than its factorization.

215332542121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18882022.

The product of its digits is 14400, while the sum is 31.

Adding to 215332542121 its reverse (121245233512), we get a palindrome (336577775633).

The spelling of 215332542121 in words is "two hundred fifteen billion, three hundred thirty-two million, five hundred forty-two thousand, one hundred twenty-one".