215031400065 has 24 divisors (see below), whose sum is σ = 372734812008. Its totient is φ = 114679192320.

The previous prime is 215031400043. The next prime is 215031400081. The reversal of 215031400065 is 560004130512.

It can be written as a sum of positive squares in 4 ways, for example, as 1773083664 + 213258316401 = 42108^2 + 461799^2 .

It is not a de Polignac number, because 215031400065 - 2¹⁷ = 215031268993 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1439997 + ... + 1582293.

It is an arithmetic number, because the mean of its divisors is an integer number (15530617167).

Almost surely, 2^215031400065 is an apocalyptic number.

It is an amenable number.

215031400065 is a deficient number, since it is larger than the sum of its proper divisors (157703411943).

215031400065 is a wasteful number, since it uses less digits than its factorization.

215031400065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175889 (or 175886 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 215031400065 its reverse (560004130512), we get a palindrome (775035530577).

The spelling of 215031400065 in words is "two hundred fifteen billion, thirty-one million, four hundred thousand, sixty-five".