21954078468 has 36 divisors (see below), whose sum is σ = 63422894080. Its totient is φ = 6272593776.

The previous prime is 21954078439. The next prime is 21954078493. The reversal of 21954078468 is 86487045912.

It is a happy number.

21954078468 is a `hidden beast` number, since 2 + 19 + 540 + 7 + 84 + 6 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×21954078468² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43559428 + ... + 43559931.

Almost surely, 2^21954078468 is an apocalyptic number.

21954078468 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21954078468 is an abundant number, since it is smaller than the sum of its proper divisors (41468815612).

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

21954078468 is a wasteful number, since it uses less digits than its factorization.

21954078468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87119376 (or 87119371 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 54.

The spelling of 21954078468 in words is "twenty-one billion, nine hundred fifty-four million, seventy-eight thousand, four hundred sixty-eight".