20407887497 has 4 divisors (see below), whose sum is σ = 20455238016. Its totient is φ = 20360536980.

The previous prime is 20407887469. The next prime is 20407887503. The reversal of 20407887497 is 79478870402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20407887497 - 2¹² = 20407883401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20407887407) 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, 23674613 + ... + 23675474.

It is an arithmetic number, because the mean of its divisors is an integer number (5113809504).

Almost surely, 2^20407887497 is an apocalyptic number.

It is an amenable number.

20407887497 is a deficient number, since it is larger than the sum of its proper divisors (47350519).

20407887497 is an equidigital number, since it uses as much as digits as its factorization.

20407887497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47350518.

The product of its (nonzero) digits is 6322176, while the sum is 56.

The spelling of 20407887497 in words is "twenty billion, four hundred seven million, eight hundred eighty-seven thousand, four hundred ninety-seven".