978992405 has 4 divisors (see below), whose sum is σ = 1174790892. Its totient is φ = 783193920.

The previous prime is 978992363. The next prime is 978992407. The reversal of 978992405 is 504299879.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 195496324 + 783496081 = 13982^2 + 27991^2 .

It is not a de Polignac number, because 978992405 - 2⁶ = 978992341 is a prime.

It is a super-2 number, since 2×978992405² = 1916852258095368050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978992407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97899236 + ... + 97899245.

It is an arithmetic number, because the mean of its divisors is an integer number (293697723).

Almost surely, 2^978992405 is an apocalyptic number.

It is an amenable number.

978992405 is a deficient number, since it is larger than the sum of its proper divisors (195798487).

978992405 is a wasteful number, since it uses less digits than its factorization.

978992405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195798486.

The product of its (nonzero) digits is 1632960, while the sum is 53.

The square root of 978992405 is about 31288.8543254623. The cubic root of 978992405 is about 992.9478524560.

The spelling of 978992405 in words is "nine hundred seventy-eight million, nine hundred ninety-two thousand, four hundred five".