1261642415 has 16 divisors (see below), whose sum is σ = 1661506560. Its totient is φ = 912057120.

The previous prime is 1261642399. The next prime is 1261642439. The reversal of 1261642415 is 5142461621.

It is not a de Polignac number, because 1261642415 - 2⁴ = 1261642399 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59495 + ... + 77864.

It is an arithmetic number, because the mean of its divisors is an integer number (103844160).

Almost surely, 2^1261642415 is an apocalyptic number.

1261642415 is a deficient number, since it is larger than the sum of its proper divisors (399864145).

1261642415 is a wasteful number, since it uses less digits than its factorization.

1261642415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137542.

The product of its digits is 11520, while the sum is 32.

The square root of 1261642415 is about 35519.6060648200. The cubic root of 1261642415 is about 1080.5513916799.

The spelling of 1261642415 in words is "one billion, two hundred sixty-one million, six hundred forty-two thousand, four hundred fifteen".