1321019978 has 8 divisors (see below), whose sum is σ = 1987241472. Its totient is φ = 658606156.

The previous prime is 1321019963. The next prime is 1321020013. The reversal of 1321019978 is 8799101231.

It is a happy number.

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

It is a Curzon number.

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, 951050 + ... + 952437.

It is an arithmetic number, because the mean of its divisors is an integer number (248405184).

Almost surely, 2^1321019978 is an apocalyptic number.

1321019978 is a deficient number, since it is larger than the sum of its proper divisors (666221494).

1321019978 is a wasteful number, since it uses less digits than its factorization.

1321019978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1903836.

The product of its (nonzero) digits is 27216, while the sum is 41.

The square root of 1321019978 is about 36345.8385238255. The cubic root of 1321019978 is about 1097.2437822890.

The spelling of 1321019978 in words is "one billion, three hundred twenty-one million, nineteen thousand, nine hundred seventy-eight".