2631561437 has 4 divisors (see below), whose sum is σ = 2635999740. Its totient is φ = 2627123136.

The previous prime is 2631561433. The next prime is 2631561469. The reversal of 2631561437 is 7341651362.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1480248676 + 1151312761 = 38474^2 + 33931^2 .

It is a cyclic number.

It is not a de Polignac number, because 2631561437 - 2² = 2631561433 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2631561437.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2631561433) 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, 2218262 + ... + 2219447.

It is an arithmetic number, because the mean of its divisors is an integer number (658999935).

Almost surely, 2^2631561437 is an apocalyptic number.

It is an amenable number.

2631561437 is a deficient number, since it is larger than the sum of its proper divisors (4438303).

2631561437 is an equidigital number, since it uses as much as digits as its factorization.

2631561437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4438302.

The product of its digits is 90720, while the sum is 38.

The square root of 2631561437 is about 51298.7469340139. The cubic root of 2631561437 is about 1380.6104974034.

The spelling of 2631561437 in words is "two billion, six hundred thirty-one million, five hundred sixty-one thousand, four hundred thirty-seven".