21707748037 has 4 divisors (see below), whose sum is σ = 21708707980. Its totient is φ = 21706788096.

The previous prime is 21707748031. The next prime is 21707748053. The reversal of 21707748037 is 73084770712.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3730033476 + 17977714561 = 61074^2 + 134081^2 .

It is a cyclic number.

It is not a de Polignac number, because 21707748037 - 2¹⁹ = 21707223749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21707748031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 445212 + ... + 491557.

It is an arithmetic number, because the mean of its divisors is an integer number (5427176995).

Almost surely, 2^21707748037 is an apocalyptic number.

It is an amenable number.

21707748037 is a deficient number, since it is larger than the sum of its proper divisors (959943).

21707748037 is an equidigital number, since it uses as much as digits as its factorization.

21707748037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959942.

The product of its (nonzero) digits is 460992, while the sum is 46.

The spelling of 21707748037 in words is "twenty-one billion, seven hundred seven million, seven hundred forty-eight thousand, thirty-seven".