216649020 has 192 divisors, whose sum is σ = 773176320. Its totient is φ = 44126208.

The previous prime is 216649019. The next prime is 216649021. The reversal of 216649020 is 20946612.

216649020 = T₃₅₀₁ + T₃₅₀₂ + ... + T₃₅₃₅.

It is an interprime number because it is at equal distance from previous prime (216649019) and next prime (216649021).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216649021) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 134862 + ... + 136458.

It is an arithmetic number, because the mean of its divisors is an integer number (4026960).

Almost surely, 2^216649020 is an apocalyptic number.

216649020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216649020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386588160).

216649020 is an abundant number, since it is smaller than the sum of its proper divisors (556527300).

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

216649020 is a wasteful number, since it uses less digits than its factorization.

216649020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1652 (or 1650 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 216649020 is about 14719.0020042121. The cubic root of 216649020 is about 600.6003435568.

The spelling of 216649020 in words is "two hundred sixteen million, six hundred forty-nine thousand, twenty".