21958339826 has 4 divisors (see below), whose sum is σ = 32937509742. Its totient is φ = 10979169912.

The previous prime is 21958339787. The next prime is 21958339829. The reversal of 21958339826 is 62893385912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21477195601 + 481144225 = 146551^2 + 21935^2 .

It is not an unprimeable number, because it can be changed into a prime (21958339829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5489584955 + ... + 5489584958.

Almost surely, 2^21958339826 is an apocalyptic number.

21958339826 is a deficient number, since it is larger than the sum of its proper divisors (10979169916).

21958339826 is a wasteful number, since it uses less digits than its factorization.

21958339826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10979169915.

The product of its digits is 5598720, while the sum is 56.

The spelling of 21958339826 in words is "twenty-one billion, nine hundred fifty-eight million, three hundred thirty-nine thousand, eight hundred twenty-six".