978691720 has 16 divisors (see below), whose sum is σ = 2202056460. Its totient is φ = 391476672.

The previous prime is 978691709. The next prime is 978691759. The reversal of 978691720 is 27196879.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 936727236 + 41964484 = 30606^2 + 6478^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12233607 + ... + 12233686.

Almost surely, 2^978691720 is an apocalyptic number.

It is an amenable number.

978691720 is an abundant number, since it is smaller than the sum of its proper divisors (1223364740).

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

978691720 is a wasteful number, since it uses less digits than its factorization.

978691720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24467304 (or 24467300 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 49.

The square root of 978691720 is about 31284.0489706815. The cubic root of 978691720 is about 992.8461849676.

The spelling of 978691720 in words is "nine hundred seventy-eight million, six hundred ninety-one thousand, seven hundred twenty".