1525640840 has 32 divisors (see below), whose sum is σ = 3459732480. Its totient is φ = 605449152.

The previous prime is 1525640773. The next prime is 1525640849. The reversal of 1525640840 is 480465251.

It is a self number, because there is not a number n which added to its sum of digits gives 1525640840.

It is not an unprimeable number, because it can be changed into a prime (1525640849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 145082 + ... + 155241.

It is an arithmetic number, because the mean of its divisors is an integer number (108116640).

Almost surely, 2^1525640840 is an apocalyptic number.

1525640840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1525640840 is an abundant number, since it is smaller than the sum of its proper divisors (1934091640).

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

1525640840 is a wasteful number, since it uses less digits than its factorization.

1525640840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300461 (or 300457 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 35.

The square root of 1525640840 is about 39059.4526331335. The cubic root of 1525640840 is about 1151.1999673705.

The spelling of 1525640840 in words is "one billion, five hundred twenty-five million, six hundred forty thousand, eight hundred forty".