127720651 has 4 divisors (see below), whose sum is σ = 131840704. Its totient is φ = 123600600.

The previous prime is 127720639. The next prime is 127720687. The reversal of 127720651 is 156027721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 156027721 = 107 ⋅1458203.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-127720651 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 4120021 = 127720651 / (1 + 2 + 7 + 7 + 2 + 0 + 6 + 5 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (127720051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2059980 + ... + 2060041.

It is an arithmetic number, because the mean of its divisors is an integer number (32960176).

Almost surely, 2^127720651 is an apocalyptic number.

127720651 is a deficient number, since it is larger than the sum of its proper divisors (4120053).

127720651 is an equidigital number, since it uses as much as digits as its factorization.

127720651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4120052.

The product of its (nonzero) digits is 5880, while the sum is 31.

The square root of 127720651 is about 11301.3561575591. The cubic root of 127720651 is about 503.6015303378.

The spelling of 127720651 in words is "one hundred twenty-seven million, seven hundred twenty thousand, six hundred fifty-one".