215450021010 has 256 divisors, whose sum is σ = 628790169600. Its totient is φ = 46151368704.

The previous prime is 215450021009. The next prime is 215450021011. The reversal of 215450021010 is 10120054512.

It is an interprime number because it is at equal distance from previous prime (215450021009) and next prime (215450021011).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (215450021011) by changing a digit.

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 127 ways as a sum of consecutive naturals, for example, 167144446 + ... + 167145734.

It is an arithmetic number, because the mean of its divisors is an integer number (2456211600).

Almost surely, 2^215450021010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215450021010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (314395084800).

215450021010 is an abundant number, since it is smaller than the sum of its proper divisors (413340148590).

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

215450021010 is a wasteful number, since it uses less digits than its factorization.

215450021010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1745.

The product of its (nonzero) digits is 400, while the sum is 21.

Adding to 215450021010 its reverse (10120054512), we get a palindrome (225570075522).

The spelling of 215450021010 in words is "two hundred fifteen billion, four hundred fifty million, twenty-one thousand, ten".