20625021497 has 4 divisors (see below), whose sum is σ = 21014172900. Its totient is φ = 20235870096.

The previous prime is 20625021457. The next prime is 20625021517. The reversal of 20625021497 is 79412052602.

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 10978638841 + 9646382656 = 104779^2 + 98216^2 .

It is a cyclic number.

It is not a de Polignac number, because 20625021497 - 2¹⁴ = 20625005113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20625021497.

It is not an unprimeable number, because it can be changed into a prime (20625021437) 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, 194575622 + ... + 194575727.

It is an arithmetic number, because the mean of its divisors is an integer number (5253543225).

Almost surely, 2^20625021497 is an apocalyptic number.

It is an amenable number.

20625021497 is a deficient number, since it is larger than the sum of its proper divisors (389151403).

20625021497 is an equidigital number, since it uses as much as digits as its factorization.

20625021497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389151402.

The product of its (nonzero) digits is 60480, while the sum is 38.

The spelling of 20625021497 in words is "twenty billion, six hundred twenty-five million, twenty-one thousand, four hundred ninety-seven".