28505497831 has 8 divisors (see below), whose sum is σ = 28551838640. Its totient is φ = 28459190592.

The previous prime is 28505497807. The next prime is 28505497837. The reversal of 28505497831 is 13879450582.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28505497831 - 2¹¹ = 28505495783 is a prime.

It is a super-2 number, since 2×28505497831² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28505497837) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2102731 + ... + 2116243.

It is an arithmetic number, because the mean of its divisors is an integer number (3568979830).

Almost surely, 2^28505497831 is an apocalyptic number.

28505497831 is a deficient number, since it is larger than the sum of its proper divisors (46340809).

28505497831 is a wasteful number, since it uses less digits than its factorization.

28505497831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16785.

The product of its (nonzero) digits is 2419200, while the sum is 52.

The spelling of 28505497831 in words is "twenty-eight billion, five hundred five million, four hundred ninety-seven thousand, eight hundred thirty-one".