631557749 has 2 divisors, whose sum is σ = 631557750. Its totient is φ = 631557748.

The previous prime is 631557733. The next prime is 631557767. The reversal of 631557749 is 947755136.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 481495249 + 150062500 = 21943^2 + 12250^2 .

It is a cyclic number.

It is not a de Polignac number, because 631557749 - 2⁴ = 631557733 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (631557049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315778874 + 315778875.

It is an arithmetic number, because the mean of its divisors is an integer number (315778875).

Almost surely, 2^631557749 is an apocalyptic number.

It is an amenable number.

631557749 is a deficient number, since it is larger than the sum of its proper divisors (1).

631557749 is an equidigital number, since it uses as much as digits as its factorization.

631557749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 793800, while the sum is 47.

The square root of 631557749 is about 25130.8127405383. The cubic root of 631557749 is about 857.9678669166.

The spelling of 631557749 in words is "six hundred thirty-one million, five hundred fifty-seven thousand, seven hundred forty-nine".