1225761520 has 20 divisors (see below), whose sum is σ = 2849895720. Its totient is φ = 490304576.

The previous prime is 1225761487. The next prime is 1225761533. The reversal of 1225761520 is 251675221.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7660930 + ... + 7661089.

It is an arithmetic number, because the mean of its divisors is an integer number (142494786).

Almost surely, 2^1225761520 is an apocalyptic number.

1225761520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1225761520 is an abundant number, since it is smaller than the sum of its proper divisors (1624134200).

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

1225761520 is a wasteful number, since it uses less digits than its factorization.

1225761520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15322032 (or 15322026 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 1225761520 is about 35010.8771669606. The cubic root of 1225761520 is about 1070.2091535123.

The spelling of 1225761520 in words is "one billion, two hundred twenty-five million, seven hundred sixty-one thousand, five hundred twenty".