215531025520042 has 16 divisors (see below), whose sum is σ = 342315903434760. Its totient is φ = 101425795550208.

The previous prime is 215531025520009. The next prime is 215531025520079. The reversal of 215531025520042 is 240025520135512.

It can be written as a sum of positive squares in 4 ways, for example, as 179314569123921 + 36216456396121 = 13390839^2 + 6018011^2 .

It is a junction number, because it is equal to n+sod(n) for n = 215531025519983 and 215531025520010.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11617263 + ... + 23791234.

Almost surely, 2^{215531025520042} is an apocalyptic number.

215531025520042 is a deficient number, since it is larger than the sum of its proper divisors (126784877914718).

215531025520042 is a wasteful number, since it uses less digits than its factorization.

215531025520042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35587545.

The product of its (nonzero) digits is 120000, while the sum is 37.

Adding to 215531025520042 its reverse (240025520135512), we get a palindrome (455556545655554).

The spelling of 215531025520042 in words is "two hundred fifteen trillion, five hundred thirty-one billion, twenty-five million, five hundred twenty thousand, forty-two".