21011326654 has 4 divisors (see below), whose sum is σ = 31516989984. Its totient is φ = 10505663326.

The previous prime is 21011326603. The next prime is 21011326657. The reversal of 21011326654 is 45662311012.

It is a happy number.

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

It is a super-2 number, since 2×21011326654² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011326657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5252831662 + ... + 5252831665.

It is an arithmetic number, because the mean of its divisors is an integer number (7879247496).

Almost surely, 2^21011326654 is an apocalyptic number.

21011326654 is a deficient number, since it is larger than the sum of its proper divisors (10505663330).

21011326654 is a wasteful number, since it uses less digits than its factorization.

21011326654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10505663329.

The product of its (nonzero) digits is 8640, while the sum is 31.

Adding to 21011326654 its reverse (45662311012), we get a palindrome (66673637666).

The spelling of 21011326654 in words is "twenty-one billion, eleven million, three hundred twenty-six thousand, six hundred fifty-four".