216787940 has 24 divisors (see below), whose sum is σ = 465843840. Its totient is φ = 84698208.

The previous prime is 216787939. The next prime is 216787943. The reversal of 216787940 is 49787612.

It is a junction number, because it is equal to n+sod(n) for n = 216787891 and 216787900.

It is not an unprimeable number, because it can be changed into a prime (216787943) 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, 125180 + ... + 126899.

It is an arithmetic number, because the mean of its divisors is an integer number (19410160).

Almost surely, 2^216787940 is an apocalyptic number.

216787940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216787940 is an abundant number, since it is smaller than the sum of its proper divisors (249055900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216787940 is a wasteful number, since it uses less digits than its factorization.

216787940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252131 (or 252129 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 216787940 is about 14723.7203179088. The cubic root of 216787940 is about 600.7286887370.

The spelling of 216787940 in words is "two hundred sixteen million, seven hundred eighty-seven thousand, nine hundred forty".