21515414310454 has 32 divisors (see below), whose sum is σ = 34808703350400. Its totient is φ = 9940533341760.

The previous prime is 21515414310451. The next prime is 21515414310539. The reversal of 21515414310454 is 45401341451512.

It is a super-2 number, since 2×21515414310454² (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 (21515414310451) 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, 4780329 + ... + 8116795.

It is an arithmetic number, because the mean of its divisors is an integer number (1087771979700).

Almost surely, 2^{21515414310454} is an apocalyptic number.

21515414310454 is a deficient number, since it is larger than the sum of its proper divisors (13293289039946).

21515414310454 is a wasteful number, since it uses less digits than its factorization.

21515414310454 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3340668.

The product of its (nonzero) digits is 192000, while the sum is 40.

Adding to 21515414310454 its reverse (45401341451512), we get a palindrome (66916755761966).

The spelling of 21515414310454 in words is "twenty-one trillion, five hundred fifteen billion, four hundred fourteen million, three hundred ten thousand, four hundred fifty-four".