213221240 has 16 divisors (see below), whose sum is σ = 479747880. Its totient is φ = 85288480.

The previous prime is 213221209. The next prime is 213221243. The reversal of 213221240 is 42122312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213221243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2665226 + ... + 2665305.

Almost surely, 2^213221240 is an apocalyptic number.

213221240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213221240 is an abundant number, since it is smaller than the sum of its proper divisors (266526640).

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

213221240 is a wasteful number, since it uses less digits than its factorization.

213221240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5330542 (or 5330538 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 213221240 is about 14602.0971096620. The cubic root of 213221240 is about 597.4159612902.

Adding to 213221240 its reverse (42122312), we get a palindrome (255343552).

The spelling of 213221240 in words is "two hundred thirteen million, two hundred twenty-one thousand, two hundred forty".