67428557 has 6 divisors (see below), whose sum is σ = 78437358. Its totient is φ = 57795864.

The previous prime is 67428553. The next prime is 67428583. The reversal of 67428557 is 75582476.

It can be written as a sum of positive squares in only one way, i.e., 44970436 + 22458121 = 6706^2 + 4739^2 .

It is not a de Polignac number, because 67428557 - 2² = 67428553 is a prime.

It is a super-2 number, since 2×67428557² = 9093220598204498, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67428553) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 687998 + ... + 688095.

It is an arithmetic number, because the mean of its divisors is an integer number (13072893).

Almost surely, 2^67428557 is an apocalyptic number.

It is an amenable number.

67428557 is a deficient number, since it is larger than the sum of its proper divisors (11008801).

67428557 is a wasteful number, since it uses less digits than its factorization.

67428557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1376107 (or 1376100 counting only the distinct ones).

The product of its digits is 470400, while the sum is 44.

The square root of 67428557 is about 8211.4893289829. The cubic root of 67428557 is about 407.0189427884.

The spelling of 67428557 in words is "sixty-seven million, four hundred twenty-eight thousand, five hundred fifty-seven".