851400720 has 200 divisors, whose sum is σ = 2994558336. Its totient is φ = 224163072.

The previous prime is 851400713. The next prime is 851400721. The reversal of 851400720 is 27004158.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (851400721) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 537049 + ... + 538631.

Almost surely, 2^851400720 is an apocalyptic number.

851400720 is a gapful number since it is divisible by the number (80) 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 851400720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1497279168).

851400720 is an abundant number, since it is smaller than the sum of its proper divisors (2143157616).

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

851400720 is a wasteful number, since it uses less digits than its factorization.

851400720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691 (or 1676 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 851400720 is about 29178.7717356300. The cubic root of 851400720 is about 947.7882879256.

Adding to 851400720 its reverse (27004158), we get a palindrome (878404878).

The spelling of 851400720 in words is "eight hundred fifty-one million, four hundred thousand, seven hundred twenty".