978321531 has 8 divisors (see below), whose sum is σ = 1423013184. Its totient is φ = 592922120.

The previous prime is 978321517. The next prime is 978321563. The reversal of 978321531 is 135123879.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 978321531 - 2¹⁵ = 978288763 is a prime.

It is a super-2 number, since 2×978321531² = 1914226036036367922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 978321531.

It is not an unprimeable number, because it can be changed into a prime (978321511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14823021 + ... + 14823086.

It is an arithmetic number, because the mean of its divisors is an integer number (177876648).

Almost surely, 2^978321531 is an apocalyptic number.

978321531 is a deficient number, since it is larger than the sum of its proper divisors (444691653).

978321531 is a wasteful number, since it uses less digits than its factorization.

978321531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29646121.

The product of its digits is 45360, while the sum is 39.

The square root of 978321531 is about 31278.1318335990. The cubic root of 978321531 is about 992.7209882111.

The spelling of 978321531 in words is "nine hundred seventy-eight million, three hundred twenty-one thousand, five hundred thirty-one".