216909420 has 96 divisors (see below), whose sum is σ = 747522048. Its totient is φ = 45764352.

The previous prime is 216909401. The next prime is 216909439. The reversal of 216909420 is 24909612.

It is an interprime number because it is at equal distance from previous prime (216909401) and next prime (216909439).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14404 + ... + 25323.

It is an arithmetic number, because the mean of its divisors is an integer number (7786688).

Almost surely, 2^216909420 is an apocalyptic number.

216909420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216909420 is an abundant number, since it is smaller than the sum of its proper divisors (530612628).

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

216909420 is a wasteful number, since it uses less digits than its factorization.

216909420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39759 (or 39757 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 216909420 is about 14727.8450562192. The cubic root of 216909420 is about 600.8408765494.

The spelling of 216909420 in words is "two hundred sixteen million, nine hundred nine thousand, four hundred twenty".