761721840 has 160 divisors (see below), whose sum is σ = 2862316800. Its totient is φ = 184654080.

The previous prime is 761721833. The next prime is 761721847. The reversal of 761721840 is 48127167.

It is an interprime number because it is at equal distance from previous prime (761721833) and next prime (761721847).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 761721795 and 761721804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (761721847) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7731 + ... + 39789.

It is an arithmetic number, because the mean of its divisors is an integer number (17889480).

Almost surely, 2^761721840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 761721840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1431158400).

761721840 is an abundant number, since it is smaller than the sum of its proper divisors (2100594960).

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

761721840 is a wasteful number, since it uses less digits than its factorization.

761721840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32092 (or 32080 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 761721840 is about 27599.3086869943. The cubic root of 761721840 is about 913.2691816818.

The spelling of 761721840 in words is "seven hundred sixty-one million, seven hundred twenty-one thousand, eight hundred forty".