21948324251 has 8 divisors (see below), whose sum is σ = 25137515520. Its totient is φ = 18772562088.

The previous prime is 21948324199. The next prime is 21948324269. The reversal of 21948324251 is 15242384912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21948324251 - 2³⁴ = 4768455067 is a prime.

It is a super-2 number, since 2×21948324251² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21948324199 and 21948324208.

It is not an unprimeable number, because it can be changed into a prime (21948324271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3353771 + ... + 3360308.

It is an arithmetic number, because the mean of its divisors is an integer number (3142189440).

Almost surely, 2^21948324251 is an apocalyptic number.

21948324251 is a deficient number, since it is larger than the sum of its proper divisors (3189191269).

21948324251 is an equidigital number, since it uses as much as digits as its factorization.

21948324251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6714553.

The product of its digits is 138240, while the sum is 41.

The spelling of 21948324251 in words is "twenty-one billion, nine hundred forty-eight million, three hundred twenty-four thousand, two hundred fifty-one".