215685420455 has 32 divisors (see below), whose sum is σ = 266358201984. Its totient is φ = 167593660416.

The previous prime is 215685420443. The next prime is 215685420481. The reversal of 215685420455 is 554024586512.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215685420455 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28054622 + ... + 28062308.

It is an arithmetic number, because the mean of its divisors is an integer number (8323693812).

Almost surely, 2^215685420455 is an apocalyptic number.

215685420455 is a deficient number, since it is larger than the sum of its proper divisors (50672781529).

215685420455 is a wasteful number, since it uses less digits than its factorization.

215685420455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8795.

The product of its (nonzero) digits is 1920000, while the sum is 47.

The spelling of 215685420455 in words is "two hundred fifteen billion, six hundred eighty-five million, four hundred twenty thousand, four hundred fifty-five".