213561621000 has 768 divisors, whose sum is σ = 897087260160. Its totient is φ = 44619724800.

The previous prime is 213561620971. The next prime is 213561621029. The reversal of 213561621000 is 126165312.

213561621000 is a `hidden beast` number, since 2 + 1 + 35 + 6 + 1 + 621 + 0 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (213561620971) and next prime (213561621029).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 87631782 + ... + 87634218.

It is an arithmetic number, because the mean of its divisors is an integer number (1168082370).

Almost surely, 2^213561621000 is an apocalyptic number.

213561621000 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 213561621000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (448543630080).

213561621000 is an abundant number, since it is smaller than the sum of its proper divisors (683525639160).

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

213561621000 is a wasteful number, since it uses less digits than its factorization.

213561621000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2591 (or 2574 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

Adding to 213561621000 its reverse (126165312), we get a palindrome (213687786312).

The spelling of 213561621000 in words is "two hundred thirteen billion, five hundred sixty-one million, six hundred twenty-one thousand".