691700156421 has 8 divisors (see below), whose sum is σ = 928456586400. Its totient is φ = 458038582032.

The previous prime is 691700156419. The next prime is 691700156423. The reversal of 691700156421 is 124651007196.

It is an interprime number because it is at equal distance from previous prime (691700156419) and next prime (691700156423).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 691700156421 - 2¹ = 691700156419 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691700156423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 773713375 + ... + 773714268.

It is an arithmetic number, because the mean of its divisors is an integer number (116057073300).

Almost surely, 2^691700156421 is an apocalyptic number.

It is an amenable number.

691700156421 is a deficient number, since it is larger than the sum of its proper divisors (236756429979).

691700156421 is a wasteful number, since it uses less digits than its factorization.

691700156421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1547427795.

The product of its (nonzero) digits is 90720, while the sum is 42.

The spelling of 691700156421 in words is "six hundred ninety-one billion, seven hundred million, one hundred fifty-six thousand, four hundred twenty-one".