2601561400 has 48 divisors (see below), whose sum is σ = 6060482640. Its totient is φ = 1038585600.

The previous prime is 2601561359. The next prime is 2601561407. The reversal of 2601561400 is 41651062.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2601561407) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91717 + ... + 116683.

It is an arithmetic number, because the mean of its divisors is an integer number (126260055).

Almost surely, 2^2601561400 is an apocalyptic number.

2601561400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2601561400 is an abundant number, since it is smaller than the sum of its proper divisors (3458921240).

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

2601561400 is a wasteful number, since it uses less digits than its factorization.

2601561400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25504 (or 25495 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 2601561400 is about 51005.5036246090. The cubic root of 2601561400 is about 1375.3440725716.

It can be divided in two parts, 2601 and 561400, that added together give a square (564001 = 751²).

The spelling of 2601561400 in words is "two billion, six hundred one million, five hundred sixty-one thousand, four hundred".