1372737661 has 4 divisors (see below), whose sum is σ = 1372972192. Its totient is φ = 1372503132.

The previous prime is 1372737659. The next prime is 1372737677. The reversal of 1372737661 is 1667372731.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1667372731 = 463 ⋅3601237.

It is a cyclic number.

It is not a de Polignac number, because 1372737661 - 2¹ = 1372737659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1372737761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108255 + ... + 120268.

It is an arithmetic number, because the mean of its divisors is an integer number (343243048).

Almost surely, 2^1372737661 is an apocalyptic number.

It is an amenable number.

1372737661 is a deficient number, since it is larger than the sum of its proper divisors (234531).

1372737661 is an equidigital number, since it uses as much as digits as its factorization.

1372737661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234530.

The product of its digits is 222264, while the sum is 43.

The square root of 1372737661 is about 37050.4745043839. The cubic root of 1372737661 is about 1111.3798442098.

The spelling of 1372737661 in words is "one billion, three hundred seventy-two million, seven hundred thirty-seven thousand, six hundred sixty-one".