21927391254 has 48 divisors (see below), whose sum is σ = 49351152240. Its totient is φ = 7305865956.

The previous prime is 21927391249. The next prime is 21927391331. The reversal of 21927391254 is 45219372912.

21927391254 is a `hidden beast` number, since 2 + 1 + 9 + 2 + 7 + 391 + 254 = 666.

It is a super-3 number, since 3×21927391254³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9792267 + ... + 9794505.

It is an arithmetic number, because the mean of its divisors is an integer number (1028149005).

Almost surely, 2^21927391254 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21927391254, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24675576120).

21927391254 is an abundant number, since it is smaller than the sum of its proper divisors (27423760986).

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

21927391254 is an frugal number, since it uses more digits than its factorization.

21927391254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4501 (or 2244 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The spelling of 21927391254 in words is "twenty-one billion, nine hundred twenty-seven million, three hundred ninety-one thousand, two hundred fifty-four".