1385611978 has 16 divisors (see below), whose sum is σ = 2120344200. Its totient is φ = 678951936.

The previous prime is 1385611973. The next prime is 1385612003. The reversal of 1385611978 is 8791165831.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 819505129 + 566106849 = 28627^2 + 23793^2 .

It is not an unprimeable number, because it can be changed into a prime (1385611973) 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, 7303 + ... + 53146.

Almost surely, 2^1385611978 is an apocalyptic number.

1385611978 is a deficient number, since it is larger than the sum of its proper divisors (734732222).

1385611978 is a wasteful number, since it uses less digits than its factorization.

1385611978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60681.

The product of its digits is 362880, while the sum is 49.

The square root of 1385611978 is about 37223.8092892170. The cubic root of 1385611978 is about 1114.8434236220.

The spelling of 1385611978 in words is "one billion, three hundred eighty-five million, six hundred eleven thousand, nine hundred seventy-eight".