51557430 has 64 divisors (see below), whose sum is σ = 134120448. Its totient is φ = 12633600.

The previous prime is 51557423. The next prime is 51557501. The reversal of 51557430 is 3475515.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

It is a congruent number.

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, 20755 + ... + 23105.

It is an arithmetic number, because the mean of its divisors is an integer number (2095632).

Almost surely, 2^51557430 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51557430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67060224).

51557430 is an abundant number, since it is smaller than the sum of its proper divisors (82563018).

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

51557430 is a wasteful number, since it uses less digits than its factorization.

51557430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2421.

The product of its (nonzero) digits is 10500, while the sum is 30.

The square root of 51557430 is about 7180.3502700077. The cubic root of 51557430 is about 372.1891886561.

The spelling of 51557430 in words is "fifty-one million, five hundred fifty-seven thousand, four hundred thirty".