1551728 has 20 divisors (see below), whose sum is σ = 3025848. Its totient is φ = 770880.

The previous prime is 1551707. The next prime is 1551731. The reversal of 1551728 is 8271551.

It is a super-8 number, since 8×1551728⁸ (a number of 51 digits) contains 88888888 as substring.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1551728.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4523 + ... + 4853.

2^1551728 is an apocalyptic number.

It is an amenable number.

1551728 is a deficient number, since it is larger than the sum of its proper divisors (1474120).

1551728 is a wasteful number, since it uses less digits than its factorization.

1551728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632 (or 626 counting only the distinct ones).

The product of its digits is 2800, while the sum is 29.

The square root of 1551728 is about 1245.6837479874. The cubic root of 1551728 is about 115.7724433123.

The spelling of 1551728 in words is "one million, five hundred fifty-one thousand, seven hundred twenty-eight".