28155230978972 has 6 divisors (see below), whose sum is σ = 49271654213208. Its totient is φ = 14077615489484.

The previous prime is 28155230978957. The next prime is 28155230979049. The reversal of 28155230978972 is 27987903255182.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3519403872368 + ... + 3519403872375.

It is an arithmetic number, because the mean of its divisors is an integer number (8211942368868).

Almost surely, 2^{28155230978972} is an apocalyptic number.

It is an amenable number.

28155230978972 is a deficient number, since it is larger than the sum of its proper divisors (21116423234236).

28155230978972 is a wasteful number, since it uses less digits than its factorization.

28155230978972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7038807744747 (or 7038807744745 counting only the distinct ones).

The product of its (nonzero) digits is 152409600, while the sum is 68.

The spelling of 28155230978972 in words is "twenty-eight trillion, one hundred fifty-five billion, two hundred thirty million, nine hundred seventy-eight thousand, nine hundred seventy-two".