1557072231 has 32 divisors (see below), whose sum is σ = 2441795328. Its totient is φ = 870109440.

The previous prime is 1557072199. The next prime is 1557072299. The reversal of 1557072231 is 1322707551.

It is a happy number.

It is not a de Polignac number, because 1557072231 - 2⁵ = 1557072199 is a prime.

It is a super-2 number, since 2×1557072231² = 4848947865102634722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 1557072192 and 1557072201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1557072131) 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, 559315 + ... + 562091.

It is an arithmetic number, because the mean of its divisors is an integer number (76306104).

Almost surely, 2^1557072231 is an apocalyptic number.

1557072231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1557072231 is a deficient number, since it is larger than the sum of its proper divisors (884723097).

1557072231 is a wasteful number, since it uses less digits than its factorization.

1557072231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4111.

The product of its (nonzero) digits is 14700, while the sum is 33.

The square root of 1557072231 is about 39459.7545734892. The cubic root of 1557072231 is about 1159.0519977078.

Adding to 1557072231 its reverse (1322707551), we get a palindrome (2879779782).

The spelling of 1557072231 in words is "one billion, five hundred fifty-seven million, seventy-two thousand, two hundred thirty-one".