1057991436 has 96 divisors (see below), whose sum is σ = 2897664000. Its totient is φ = 333305280.

The previous prime is 1057991423. The next prime is 1057991437. The reversal of 1057991436 is 6341997501.

It is a super-2 number, since 2×1057991436² = 2238691757298684192, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1057991391 and 1057991400.

It is not an unprimeable number, because it can be changed into a prime (1057991437) 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 31 ways as a sum of consecutive naturals, for example, 140290 + ... + 147638.

It is an arithmetic number, because the mean of its divisors is an integer number (30184000).

Almost surely, 2^1057991436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1057991436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1448832000).

1057991436 is an abundant number, since it is smaller than the sum of its proper divisors (1839672564).

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

1057991436 is a wasteful number, since it uses less digits than its factorization.

1057991436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7436 (or 7428 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 45.

The square root of 1057991436 is about 32526.7802894784. The cubic root of 1057991436 is about 1018.9684033935.

The spelling of 1057991436 in words is "one billion, fifty-seven million, nine hundred ninety-one thousand, four hundred thirty-six".