691896791040 has 832 divisors, whose sum is σ = 2783704928256. Its totient is φ = 142822342656.

The previous prime is 691896791017. The next prime is 691896791051. The reversal of 691896791040 is 40197698196.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (832).

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 262777564 + ... + 262780196.

Almost surely, 2^691896791040 is an apocalyptic number.

691896791040 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 691896791040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1391852464128).

691896791040 is an abundant number, since it is smaller than the sum of its proper divisors (2091808137216).

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

691896791040 is a wasteful number, since it uses less digits than its factorization.

691896791040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2732 (or 2710 counting only the distinct ones).

The product of its (nonzero) digits is 5878656, while the sum is 60.

The spelling of 691896791040 in words is "six hundred ninety-one billion, eight hundred ninety-six million, seven hundred ninety-one thousand, forty".