1157564721 has 16 divisors (see below), whose sum is σ = 1668564800. Its totient is φ = 711332928.

The previous prime is 1157564717. The next prime is 1157564747. The reversal of 1157564721 is 1274657511.

It is not a de Polignac number, because 1157564721 - 2² = 1157564717 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1157564721.

It is not an unprimeable number, because it can be changed into a prime (1157564701) 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, 272326 + ... + 276543.

It is an arithmetic number, because the mean of its divisors is an integer number (104285300).

Almost surely, 2^1157564721 is an apocalyptic number.

It is an amenable number.

1157564721 is a deficient number, since it is larger than the sum of its proper divisors (511000079).

1157564721 is a wasteful number, since it uses less digits than its factorization.

1157564721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548928.

The product of its digits is 58800, while the sum is 39.

The square root of 1157564721 is about 34023.0028216206. The cubic root of 1157564721 is about 1049.9817747403.

The spelling of 1157564721 in words is "one billion, one hundred fifty-seven million, five hundred sixty-four thousand, seven hundred twenty-one".