1251652665 has 8 divisors (see below), whose sum is σ = 2002644288. Its totient is φ = 667548080.

The previous prime is 1251652651. The next prime is 1251652669. The reversal of 1251652665 is 5662561521.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1251652665 - 2⁹ = 1251652153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1251652669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41721741 + ... + 41721770.

It is an arithmetic number, because the mean of its divisors is an integer number (250330536).

Almost surely, 2^1251652665 is an apocalyptic number.

1251652665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1251652665 is a deficient number, since it is larger than the sum of its proper divisors (750991623).

1251652665 is an equidigital number, since it uses as much as digits as its factorization.

1251652665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83443519.

The product of its digits is 108000, while the sum is 39.

The square root of 1251652665 is about 35378.7035517131. The cubic root of 1251652665 is about 1077.6918771203.

The spelling of 1251652665 in words is "one billion, two hundred fifty-one million, six hundred fifty-two thousand, six hundred sixty-five".