3947820660 has 96 divisors (see below), whose sum is σ = 14036709120. Its totient is φ = 902358144.

The previous prime is 3947820649. The next prime is 3947820661. The reversal of 3947820660 is 660287493.

It is a super-3 number, since 3×3947820660³ (a number of 30 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3947820661) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 518419 + ... + 525978.

It is an arithmetic number, because the mean of its divisors is an integer number (146215720).

Almost surely, 2^3947820660 is an apocalyptic number.

3947820660 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3947820660 is an abundant number, since it is smaller than the sum of its proper divisors (10088888460).

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

3947820660 is a wasteful number, since it uses less digits than its factorization.

3947820660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044422 (or 1044414 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 3947820660 is about 62831.6851596390. The cubic root of 3947820660 is about 1580.4683571194.

The spelling of 3947820660 in words is "three billion, nine hundred forty-seven million, eight hundred twenty thousand, six hundred sixty".