28377649081 has 8 divisors (see below), whose sum is σ = 28411801928. Its totient is φ = 28343520000.

The previous prime is 28377649039. The next prime is 28377649099. The reversal of 28377649081 is 18094677382.

It can be written as a sum of positive squares in 4 ways, for example, as 19576207225 + 8801441856 = 139915^2 + 93816^2 .

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

It is a 4-Lehmer number, since φ(28377649081) divides (28377649081-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 28377649081 - 2⁷ = 28377648953 is a prime.

It is a super-2 number, since 2×28377649081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28377649031) 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, 3498931 + ... + 3507031.

It is an arithmetic number, because the mean of its divisors is an integer number (3551475241).

Almost surely, 2^28377649081 is an apocalyptic number.

It is an amenable number.

28377649081 is a deficient number, since it is larger than the sum of its proper divisors (34152847).

28377649081 is a wasteful number, since it uses less digits than its factorization.

28377649081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11883.

The product of its (nonzero) digits is 4064256, while the sum is 55.

The spelling of 28377649081 in words is "twenty-eight billion, three hundred seventy-seven million, six hundred forty-nine thousand, eighty-one".