216021646438 has 16 divisors (see below), whose sum is σ = 349272750960. Its totient is φ = 99612382176.

The previous prime is 216021646433. The next prime is 216021646469. The reversal of 216021646438 is 834646120612.

It is a junction number, because it is equal to n+sod(n) for n = 216021646394 and 216021646403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216021646433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3717120 + ... + 3774787.

It is an arithmetic number, because the mean of its divisors is an integer number (21829546935).

Almost surely, 2^216021646438 is an apocalyptic number.

216021646438 is a deficient number, since it is larger than the sum of its proper divisors (133251104522).

216021646438 is a wasteful number, since it uses less digits than its factorization.

216021646438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7493031.

The product of its (nonzero) digits is 331776, while the sum is 43.

The spelling of 216021646438 in words is "two hundred sixteen billion, twenty-one million, six hundred forty-six thousand, four hundred thirty-eight".