647377881 has 8 divisors (see below), whose sum is σ = 879456960. Its totient is φ = 423442032.

The previous prime is 647377877. The next prime is 647377897. The reversal of 647377881 is 188773746.

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

It is not a de Polignac number, because 647377881 - 2² = 647377877 is a prime.

It is a super-2 number, since 2×647377881² = 838196241616100322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (647377831) 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, 2035621 + ... + 2035938.

It is an arithmetic number, because the mean of its divisors is an integer number (109932120).

Almost surely, 2^647377881 is an apocalyptic number.

It is an amenable number.

647377881 is a deficient number, since it is larger than the sum of its proper divisors (232079079).

647377881 is a wasteful number, since it uses less digits than its factorization.

647377881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4071615.

The product of its digits is 1580544, while the sum is 51.

The square root of 647377881 is about 25443.6216172148. The cubic root of 647377881 is about 865.0727242363.

The spelling of 647377881 in words is "six hundred forty-seven million, three hundred seventy-seven thousand, eight hundred eighty-one".