21154454023 has 8 divisors (see below), whose sum is σ = 22271839920. Its totient is φ = 20037467520.

The previous prime is 21154454003. The next prime is 21154454029. The reversal of 21154454023 is 32045445112.

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 21154454023 - 2¹³ = 21154445831 is a prime.

It is a super-2 number, since 2×21154454023² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154454029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12111 + ... + 206047.

It is an arithmetic number, because the mean of its divisors is an integer number (2783979990).

Almost surely, 2^21154454023 is an apocalyptic number.

21154454023 is a deficient number, since it is larger than the sum of its proper divisors (1117385897).

21154454023 is a wasteful number, since it uses less digits than its factorization.

21154454023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199697.

The product of its (nonzero) digits is 19200, while the sum is 31.

Adding to 21154454023 its reverse (32045445112), we get a palindrome (53199899135).

The spelling of 21154454023 in words is "twenty-one billion, one hundred fifty-four million, four hundred fifty-four thousand, twenty-three".