1157721006 has 64 divisors (see below), whose sum is σ = 2618380800. Its totient is φ = 338760576.

The previous prime is 1157721001. The next prime is 1157721011. The reversal of 1157721006 is 6001277511.

It is an interprime number because it is at equal distance from previous prime (1157721001) and next prime (1157721011).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1157721001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 147735 + ... + 155373.

It is an arithmetic number, because the mean of its divisors is an integer number (40912200).

Almost surely, 2^1157721006 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1157721006, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1309190400).

1157721006 is an abundant number, since it is smaller than the sum of its proper divisors (1460659794).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1157721006 is a wasteful number, since it uses less digits than its factorization.

1157721006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7753.

The product of its (nonzero) digits is 2940, while the sum is 30.

The square root of 1157721006 is about 34025.2994990492. The cubic root of 1157721006 is about 1050.0290259550.

Adding to 1157721006 its reverse (6001277511), we get a palindrome (7158998517).

The spelling of 1157721006 in words is "one billion, one hundred fifty-seven million, seven hundred twenty-one thousand, six".