21215220642519 has 16 divisors (see below), whose sum is σ = 28553398829568. Its totient is φ = 14010280644672.

The previous prime is 21215220642439. The next prime is 21215220642547. The reversal of 21215220642519 is 91524602251212.

It is not a de Polignac number, because 21215220642519 - 2⁸ = 21215220642263 is a prime.

It is a super-2 number, since 2×21215220642519² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21215220642919) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2038659 + ... + 6825435.

It is an arithmetic number, because the mean of its divisors is an integer number (1784587426848).

Almost surely, 2^{21215220642519} is an apocalyptic number.

21215220642519 is a deficient number, since it is larger than the sum of its proper divisors (7338178187049).

21215220642519 is a wasteful number, since it uses less digits than its factorization.

21215220642519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4800694.

The product of its (nonzero) digits is 172800, while the sum is 42.

The spelling of 21215220642519 in words is "twenty-one trillion, two hundred fifteen billion, two hundred twenty million, six hundred forty-two thousand, five hundred nineteen".