215142421 has 8 divisors (see below), whose sum is σ = 231890400. Its totient is φ = 198422832.

The previous prime is 215142419. The next prime is 215142451. The reversal of 215142421 is 124241512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 215142421 - 2¹ = 215142419 is a prime.

It is a super-2 number, since 2×215142421² = 92572522627482482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 215142392 and 215142401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215142401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10230 + ... + 23128.

It is an arithmetic number, because the mean of its divisors is an integer number (28986300).

Almost surely, 2^215142421 is an apocalyptic number.

It is an amenable number.

215142421 is a deficient number, since it is larger than the sum of its proper divisors (16747979).

215142421 is a wasteful number, since it uses less digits than its factorization.

215142421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14195.

The product of its digits is 640, while the sum is 22.

The square root of 215142421 is about 14667.7340104053. The cubic root of 215142421 is about 599.2048921750.

Adding to 215142421 its reverse (124241512), we get a palindrome (339383933).

Subtracting from 215142421 its reverse (124241512), we obtain a palindrome (90900909).

The spelling of 215142421 in words is "two hundred fifteen million, one hundred forty-two thousand, four hundred twenty-one".