1557664745 has 32 divisors (see below), whose sum is σ = 2421646080. Its totient is φ = 934053120.

The previous prime is 1557664721. The next prime is 1557664769. The reversal of 1557664745 is 5474667551.

It is an interprime number because it is at equal distance from previous prime (1557664721) and next prime (1557664769).

It is not a de Polignac number, because 1557664745 - 2⁶ = 1557664681 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1557664693 and 1557664702.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 81446 + ... + 98735.

It is an arithmetic number, because the mean of its divisors is an integer number (75676440).

Almost surely, 2^1557664745 is an apocalyptic number.

It is an amenable number.

1557664745 is a deficient number, since it is larger than the sum of its proper divisors (863981335).

1557664745 is a wasteful number, since it uses less digits than its factorization.

1557664745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180225.

The product of its digits is 3528000, while the sum is 50.

The square root of 1557664745 is about 39467.2616861114. The cubic root of 1557664745 is about 1159.1989974059.

The spelling of 1557664745 in words is "one billion, five hundred fifty-seven million, six hundred sixty-four thousand, seven hundred forty-five".