1265720457 has 16 divisors (see below), whose sum is σ = 1793010240. Its totient is φ = 792695232.

The previous prime is 1265720381. The next prime is 1265720459. The reversal of 1265720457 is 7540275621.

It is not a de Polignac number, because 1265720457 - 2¹¹ = 1265718409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1265720459) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 193383 + ... + 199820.

It is an arithmetic number, because the mean of its divisors is an integer number (112063140).

Almost surely, 2^1265720457 is an apocalyptic number.

It is an amenable number.

1265720457 is a deficient number, since it is larger than the sum of its proper divisors (527289783).

1265720457 is a wasteful number, since it uses less digits than its factorization.

1265720457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393272.

The product of its (nonzero) digits is 117600, while the sum is 39.

The square root of 1265720457 is about 35576.9652584365. The cubic root of 1265720457 is about 1081.7143716775.

The spelling of 1265720457 in words is "one billion, two hundred sixty-five million, seven hundred twenty thousand, four hundred fifty-seven".