80621557 has 8 divisors (see below), whose sum is σ = 82913112. Its totient is φ = 78336000.

The previous prime is 80621551. The next prime is 80621561. The reversal of 80621557 is 75512608.

It can be written as a sum of positive squares in 4 ways, for example, as 42107121 + 38514436 = 6489^2 + 6206^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80621557 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 (80621551) 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 7 ways as a sum of consecutive naturals, for example, 49557 + ... + 51157.

It is an arithmetic number, because the mean of its divisors is an integer number (10364139).

Almost surely, 2^80621557 is an apocalyptic number.

It is an amenable number.

80621557 is a deficient number, since it is larger than the sum of its proper divisors (2291555).

80621557 is a wasteful number, since it uses less digits than its factorization.

80621557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2999.

The product of its (nonzero) digits is 16800, while the sum is 34.

The square root of 80621557 is about 8978.9507738934. The cubic root of 80621557 is about 431.9999803527. Note that the first 4 decimals are identical.

The spelling of 80621557 in words is "eighty million, six hundred twenty-one thousand, five hundred fifty-seven".