681237149 has 4 divisors (see below), whose sum is σ = 682009536. Its totient is φ = 680464764.

The previous prime is 681237133. The next prime is 681237157. The reversal of 681237149 is 941732186.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 681237149 - 2⁴ = 681237133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681237199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 384869 + ... + 386634.

It is an arithmetic number, because the mean of its divisors is an integer number (170502384).

Almost surely, 2^681237149 is an apocalyptic number.

It is an amenable number.

681237149 is a deficient number, since it is larger than the sum of its proper divisors (772387).

681237149 is an equidigital number, since it uses as much as digits as its factorization.

681237149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 772386.

The product of its digits is 72576, while the sum is 41.

The square root of 681237149 is about 26100.5200906036. The cubic root of 681237149 is about 879.8988989396.

The spelling of 681237149 in words is "six hundred eighty-one million, two hundred thirty-seven thousand, one hundred forty-nine".