1557420551 has 8 divisors (see below), whose sum is σ = 1625537760. Its totient is φ = 1489336992.

The previous prime is 1557420511. The next prime is 1557420583. The reversal of 1557420551 is 1550247551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1557420551 - 2¹⁰ = 1557419527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1557420511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149261 + ... + 159353.

It is an arithmetic number, because the mean of its divisors is an integer number (203192220).

Almost surely, 2^1557420551 is an apocalyptic number.

1557420551 is a deficient number, since it is larger than the sum of its proper divisors (68117209).

1557420551 is a wasteful number, since it uses less digits than its factorization.

1557420551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16825.

The product of its (nonzero) digits is 35000, while the sum is 35.

The square root of 1557420551 is about 39464.1679375101. The cubic root of 1557420551 is about 1159.1384186379.

The spelling of 1557420551 in words is "one billion, five hundred fifty-seven million, four hundred twenty thousand, five hundred fifty-one".