691338240 has 220 divisors, whose sum is σ = 2478851496. Its totient is φ = 184246272.

The previous prime is 691338239. The next prime is 691338247. The reversal of 691338240 is 42833196.

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 = 691338195 and 691338204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691338247) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 413887 + ... + 415553.

Almost surely, 2^691338240 is an apocalyptic number.

691338240 is a gapful number since it is divisible by the number (60) 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 691338240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1239425748).

691338240 is an abundant number, since it is smaller than the sum of its proper divisors (1787513256).

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

691338240 is a wasteful number, since it uses less digits than its factorization.

691338240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1704 (or 1677 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 691338240 is about 26293.3116970837. The cubic root of 691338240 is about 884.2265002485.

The spelling of 691338240 in words is "six hundred ninety-one million, three hundred thirty-eight thousand, two hundred forty".