21308812037 has 16 divisors (see below), whose sum is σ = 22739080320. Its totient is φ = 19910952000.

The previous prime is 21308812033. The next prime is 21308812039. The reversal of 21308812037 is 73021880312.

It is a cyclic number.

It is not a de Polignac number, because 21308812037 - 2² = 21308812033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21308811988 and 21308812006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21308812033) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 483587 + ... + 525807.

It is an arithmetic number, because the mean of its divisors is an integer number (1421192520).

Almost surely, 2^21308812037 is an apocalyptic number.

It is an amenable number.

21308812037 is a deficient number, since it is larger than the sum of its proper divisors (1430268283).

21308812037 is a wasteful number, since it uses less digits than its factorization.

21308812037 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42604.

The product of its (nonzero) digits is 16128, while the sum is 35.

The spelling of 21308812037 in words is "twenty-one billion, three hundred eight million, eight hundred twelve thousand, thirty-seven".