21515453411154 has 32 divisors (see below), whose sum is σ = 44194357546560. Its totient is φ = 6977913325632.

The previous prime is 21515453411147. The next prime is 21515453411159. The reversal of 21515453411154 is 45111435451512.

It is a super-2 number, since 2×21515453411154² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21515453411159) 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, 23886577 + ... + 24770939.

It is an arithmetic number, because the mean of its divisors is an integer number (1381073673330).

Almost surely, 2^{21515453411154} is an apocalyptic number.

21515453411154 is an abundant number, since it is smaller than the sum of its proper divisors (22678904135406).

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

21515453411154 is a wasteful number, since it uses less digits than its factorization.

21515453411154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993994.

The product of its digits is 240000, while the sum is 42.

Adding to 21515453411154 its reverse (45111435451512), we get a palindrome (66626888862666).

The spelling of 21515453411154 in words is "twenty-one trillion, five hundred fifteen billion, four hundred fifty-three million, four hundred eleven thousand, one hundred fifty-four".