216402187949 has 4 divisors (see below), whose sum is σ = 216600178236. Its totient is φ = 216204197664.

The previous prime is 216402187943. The next prime is 216402187961. The reversal of 216402187949 is 949781204612.

216402187949 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 203507449924 + 12894738025 = 451118^2 + 113555^2 .

It is a cyclic number.

It is not a de Polignac number, because 216402187949 - 2⁸ = 216402187693 is a prime.

It is a super-2 number, since 2×216402187949² (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 216402187949.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216402187943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98993504 + ... + 98995689.

It is an arithmetic number, because the mean of its divisors is an integer number (54150044559).

Almost surely, 2^216402187949 is an apocalyptic number.

It is an amenable number.

216402187949 is a deficient number, since it is larger than the sum of its proper divisors (197990287).

216402187949 is a wasteful number, since it uses less digits than its factorization.

216402187949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197990286.

The product of its (nonzero) digits is 1741824, while the sum is 53.

The spelling of 216402187949 in words is "two hundred sixteen billion, four hundred two million, one hundred eighty-seven thousand, nine hundred forty-nine".