1551680 has 56 divisors (see below), whose sum is σ = 3989832. Its totient is φ = 571392.

The previous prime is 1551677. The next prime is 1551691. The reversal of 1551680 is 861551.

It can be written as a sum of positive squares in 4 ways, for example, as 33856 + 1517824 = 184^2 + 1232^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3974 + ... + 4346.

It is an arithmetic number, because the mean of its divisors is an integer number (71247).

2^1551680 is an apocalyptic number.

1551680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1551680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1994916).

1551680 is an abundant number, since it is smaller than the sum of its proper divisors (2438152).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1551680 is a wasteful number, since it uses less digits than its factorization.

1551680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403 (or 393 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 26.

The square root of 1551680 is about 1245.6644813111. The cubic root of 1551680 is about 115.7712495604.

The spelling of 1551680 in words is "one million, five hundred fifty-one thousand, six hundred eighty".