28951915969 has 4 divisors (see below), whose sum is σ = 30475701040. Its totient is φ = 27428130900.

The previous prime is 28951915939. The next prime is 28951915973. The reversal of 28951915969 is 96951915982.

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 a de Polignac number, because none of the positive numbers 2^k-28951915969 is a prime.

It is a super-2 number, since 2×28951915969² (a number of 22 digits) contains 22 as substring.

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 28951915969.

It is not an unprimeable number, because it can be changed into a prime (28951915939) 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, 761892507 + ... + 761892544.

It is an arithmetic number, because the mean of its divisors is an integer number (7618925260).

Almost surely, 2^28951915969 is an apocalyptic number.

It is an amenable number.

28951915969 is a deficient number, since it is larger than the sum of its proper divisors (1523785071).

28951915969 is a wasteful number, since it uses less digits than its factorization.

28951915969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1523785070.

The product of its digits is 15746400, while the sum is 64.

The spelling of 28951915969 in words is "twenty-eight billion, nine hundred fifty-one million, nine hundred fifteen thousand, nine hundred sixty-nine".