9978520852 has 18 divisors (see below), whose sum is σ = 18429860778. Its totient is φ = 4726667088.

The previous prime is 9978520847. The next prime is 9978520897. The reversal of 9978520852 is 2580258799.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 8303583376 + 1674937476 = 91124^2 + 40926^2 .

It is a junction number, because it is equal to n+sod(n) for n = 9978520793 and 9978520802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3453723 + ... + 3456610.

Almost surely, 2^9978520852 is an apocalyptic number.

It is an amenable number.

9978520852 is a deficient number, since it is larger than the sum of its proper divisors (8451339926).

9978520852 is a wasteful number, since it uses less digits than its factorization.

9978520852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6910375 (or 6910354 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 55.

The square root of 9978520852 is about 99892.5465287576. The cubic root of 9978520852 is about 2152.8910702638.

The spelling of 9978520852 in words is "nine billion, nine hundred seventy-eight million, five hundred twenty thousand, eight hundred fifty-two".