21214036501465 has 4 divisors (see below), whose sum is σ = 25456843801764. Its totient is φ = 16971229201168.

The previous prime is 21214036501453. The next prime is 21214036501481. The reversal of 21214036501465 is 56410563041212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2792454892096 + 18421581609369 = 1671064^2 + 4292037^2 .

It is a cyclic number.

It is not a de Polignac number, because 21214036501465 - 2³³ = 21205446566873 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2121403650142 + ... + 2121403650151.

It is an arithmetic number, because the mean of its divisors is an integer number (6364210950441).

Almost surely, 2^{21214036501465} is an apocalyptic number.

It is an amenable number.

21214036501465 is a deficient number, since it is larger than the sum of its proper divisors (4242807300299).

21214036501465 is an equidigital number, since it uses as much as digits as its factorization.

21214036501465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4242807300298.

The product of its (nonzero) digits is 172800, while the sum is 40.

Adding to 21214036501465 its reverse (56410563041212), we get a palindrome (77624599542677).

The spelling of 21214036501465 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, five hundred one thousand, four hundred sixty-five".