647764740 has 144 divisors (see below), whose sum is σ = 2300538240. Its totient is φ = 144437760.

The previous prime is 647764729. The next prime is 647764751. The reversal of 647764740 is 47467746.

It is an interprime number because it is at equal distance from previous prime (647764729) and next prime (647764751).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 45391 + ... + 57929.

It is an arithmetic number, because the mean of its divisors is an integer number (15975960).

Almost surely, 2^647764740 is an apocalyptic number.

647764740 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 647764740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1150269120).

647764740 is an abundant number, since it is smaller than the sum of its proper divisors (1652773500).

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

647764740 is a wasteful number, since it uses less digits than its factorization.

647764740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12602 (or 12597 counting only the distinct ones).

The product of its (nonzero) digits is 790272, while the sum is 45.

The square root of 647764740 is about 25451.2227604098. Note that the first 3 decimals coincide. The cubic root of 647764740 is about 865.2450061646.

It can be divided in two parts, 6477 and 64740, that added together give a palindrome (71217).

The spelling of 647764740 in words is "six hundred forty-seven million, seven hundred sixty-four thousand, seven hundred forty".