281949891978 has 16 divisors (see below), whose sum is σ = 564982131456. Its totient is φ = 93802906080.

The previous prime is 281949891967. The next prime is 281949891991. The reversal of 281949891978 is 879198949182.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45094426 + ... + 45100677.

It is an arithmetic number, because the mean of its divisors is an integer number (35311383216).

Almost surely, 2^281949891978 is an apocalyptic number.

281949891978 is an abundant number, since it is smaller than the sum of its proper divisors (283032239478).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

281949891978 is a wasteful number, since it uses less digits than its factorization.

281949891978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90195629.

The product of its digits is 188116992, while the sum is 75.

The spelling of 281949891978 in words is "two hundred eighty-one billion, nine hundred forty-nine million, eight hundred ninety-one thousand, nine hundred seventy-eight".