947220813 has 144 divisors (see below), whose sum is σ = 1877990400. Its totient is φ = 453418560.

The previous prime is 947220809. The next prime is 947220829. The reversal of 947220813 is 318022749.

It is not a de Polignac number, because 947220813 - 2² = 947220809 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (947220893) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 3963148 + ... + 3963386.

It is an arithmetic number, because the mean of its divisors is an integer number (13041600).

Almost surely, 2^947220813 is an apocalyptic number.

It is an amenable number.

947220813 is a deficient number, since it is larger than the sum of its proper divisors (930769587).

947220813 is a wasteful number, since it uses less digits than its factorization.

947220813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332 (or 322 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 947220813 is about 30776.9526269252. The cubic root of 947220813 is about 982.0880140486.

The spelling of 947220813 in words is "nine hundred forty-seven million, two hundred twenty thousand, eight hundred thirteen".