1021642505 has 16 divisors (see below), whose sum is σ = 1321717824. Its totient is φ = 753620160.

The previous prime is 1021642493. The next prime is 1021642507. The reversal of 1021642505 is 5052461201.

It is not a de Polignac number, because 1021642505 - 2²⁴ = 1004865289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021642507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55022 + ... + 71208.

It is an arithmetic number, because the mean of its divisors is an integer number (82607364).

Almost surely, 2^1021642505 is an apocalyptic number.

It is an amenable number.

1021642505 is a deficient number, since it is larger than the sum of its proper divisors (300075319).

1021642505 is a wasteful number, since it uses less digits than its factorization.

1021642505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17176.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 1021642505 is about 31963.1429149262. The cubic root of 1021642505 is about 1007.1627409805.

The spelling of 1021642505 in words is "one billion, twenty-one million, six hundred forty-two thousand, five hundred five".