1376516661 has 24 divisors (see below), whose sum is σ = 2041138080. Its totient is φ = 824181696.

The previous prime is 1376516641. The next prime is 1376516681. The reversal of 1376516661 is 1666156731.

It is a happy number.

1376516661 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1376516641) and next prime (1376516681).

It is not a de Polignac number, because 1376516661 - 2⁶ = 1376516597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1376516611) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17931 + ... + 55448.

It is an arithmetic number, because the mean of its divisors is an integer number (85047420).

Almost surely, 2^1376516661 is an apocalyptic number.

It is an amenable number.

1376516661 is a deficient number, since it is larger than the sum of its proper divisors (664621419).

1376516661 is a wasteful number, since it uses less digits than its factorization.

1376516661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73445 (or 73432 counting only the distinct ones).

The product of its digits is 136080, while the sum is 42.

The square root of 1376516661 is about 37101.4374519371. The cubic root of 1376516661 is about 1112.3987464301.

The spelling of 1376516661 in words is "one billion, three hundred seventy-six million, five hundred sixteen thousand, six hundred sixty-one".