1978876616 has 8 divisors (see below), whose sum is σ = 3710393670. Its totient is φ = 989438304.

The previous prime is 1978876583. The next prime is 1978876631. The reversal of 1978876616 is 6166788791.

It can be written as a sum of positive squares in only one way, i.e., 1931954116 + 46922500 = 43954^2 + 6850^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×1978876616² = 7831905322703222912, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123679781 + ... + 123679796.

Almost surely, 2^1978876616 is an apocalyptic number.

It is an amenable number.

1978876616 is a deficient number, since it is larger than the sum of its proper divisors (1731517054).

1978876616 is a wasteful number, since it uses less digits than its factorization.

1978876616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247359583 (or 247359579 counting only the distinct ones).

The product of its digits is 6096384, while the sum is 59.

The square root of 1978876616 is about 44484.5660426175. The cubic root of 1978876616 is about 1255.4697089967.

The spelling of 1978876616 in words is "one billion, nine hundred seventy-eight million, eight hundred seventy-six thousand, six hundred sixteen".