1557421005 has 16 divisors (see below), whose sum is σ = 2847855744. Its totient is φ = 711963840.

The previous prime is 1557421001. The next prime is 1557421007. The reversal of 1557421005 is 5001247551.

It is not a de Polignac number, because 1557421005 - 2² = 1557421001 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1557421001) 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, 7416186 + ... + 7416395.

It is an arithmetic number, because the mean of its divisors is an integer number (177990984).

Almost surely, 2^1557421005 is an apocalyptic number.

1557421005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1557421005 is a deficient number, since it is larger than the sum of its proper divisors (1290434739).

1557421005 is a wasteful number, since it uses less digits than its factorization.

1557421005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14832596.

The product of its (nonzero) digits is 7000, while the sum is 30.

The square root of 1557421005 is about 39464.1736895630. The cubic root of 1557421005 is about 1159.1385312705.

Adding to 1557421005 its reverse (5001247551), we get a palindrome (6558668556).

The spelling of 1557421005 in words is "one billion, five hundred fifty-seven million, four hundred twenty-one thousand, five".