215400801 has 16 divisors (see below), whose sum is σ = 358069248. Its totient is φ = 111896400.

The previous prime is 215400797. The next prime is 215400817. The reversal of 215400801 is 108004512.

It is not a de Polignac number, because 215400801 - 2² = 215400797 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (215400841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 466005 + ... + 466466.

It is an arithmetic number, because the mean of its divisors is an integer number (22379328).

Almost surely, 2^215400801 is an apocalyptic number.

215400801 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

215400801 is a deficient number, since it is larger than the sum of its proper divisors (142668447).

215400801 is a wasteful number, since it uses less digits than its factorization.

215400801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 932492.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 215400801 is about 14676.5391356409. The cubic root of 215400801 is about 599.4446722882. Note that the first 3 decimals are identical.

The spelling of 215400801 in words is "two hundred fifteen million, four hundred thousand, eight hundred one".