647523381 has 8 divisors (see below), whose sum is σ = 891215104. Its totient is φ = 417756960.

The previous prime is 647523367. The next prime is 647523391. The reversal of 647523381 is 183325746.

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

It is not a de Polignac number, because 647523381 - 2¹⁰ = 647522357 is a prime.

It is a super-2 number, since 2×647523381² = 838573057883342322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647523311) 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, 3481216 + ... + 3481401.

It is an arithmetic number, because the mean of its divisors is an integer number (111401888).

Almost surely, 2^647523381 is an apocalyptic number.

It is an amenable number.

647523381 is a deficient number, since it is larger than the sum of its proper divisors (243691723).

647523381 is a wasteful number, since it uses less digits than its factorization.

647523381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6962651.

The product of its digits is 120960, while the sum is 39.

The square root of 647523381 is about 25446.4807193451. The cubic root of 647523381 is about 865.1375285577.

The spelling of 647523381 in words is "six hundred forty-seven million, five hundred twenty-three thousand, three hundred eighty-one".