21111887752 has 32 divisors (see below), whose sum is σ = 39998275200. Its totient is φ = 10445831424.

The previous prime is 21111887743. The next prime is 21111887761. The reversal of 21111887752 is 25778811112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21111887743) and next prime (21111887761).

It is a super-2 number, since 2×21111887752² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21111887699 and 21111887708.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1218333 + ... + 1235539.

It is an arithmetic number, because the mean of its divisors is an integer number (1249946100).

Almost surely, 2^21111887752 is an apocalyptic number.

It is an amenable number.

21111887752 is a deficient number, since it is larger than the sum of its proper divisors (18886387448).

21111887752 is a wasteful number, since it uses less digits than its factorization.

21111887752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18805 (or 18801 counting only the distinct ones).

The product of its digits is 62720, while the sum is 43.

The spelling of 21111887752 in words is "twenty-one billion, one hundred eleven million, eight hundred eighty-seven thousand, seven hundred fifty-two".