216401653441 has 4 divisors (see below), whose sum is σ = 216437199300. Its totient is φ = 216366107584.

The previous prime is 216401653411. The next prime is 216401653451. The reversal of 216401653441 is 144356104612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 124711391025 + 91690262416 = 353145^2 + 302804^2 .

It is a cyclic number.

It is not a de Polignac number, because 216401653441 - 2²⁵ = 216368099009 is a prime.

It is a super-2 number, since 2×216401653441² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216401653441.

It is not an unprimeable number, because it can be changed into a prime (216401653411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17763796 + ... + 17775973.

It is an arithmetic number, because the mean of its divisors is an integer number (54109299825).

Almost surely, 2^216401653441 is an apocalyptic number.

It is an amenable number.

216401653441 is a deficient number, since it is larger than the sum of its proper divisors (35545859).

216401653441 is an equidigital number, since it uses as much as digits as its factorization.

216401653441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35545858.

The product of its (nonzero) digits is 69120, while the sum is 37.

The spelling of 216401653441 in words is "two hundred sixteen billion, four hundred one million, six hundred fifty-three thousand, four hundred forty-one".