20151642 has 24 divisors (see below), whose sum is σ = 46884096. Its totient is φ = 5757528.

The previous prime is 20151619. The next prime is 20151667. The reversal of 20151642 is 24615102.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33978 + ... + 34565.

It is an arithmetic number, because the mean of its divisors is an integer number (1953504).

Almost surely, 2^20151642 is an apocalyptic number.

20151642 is an abundant number, since it is smaller than the sum of its proper divisors (26732454).

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

20151642 is a wasteful number, since it uses less digits than its factorization.

20151642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68562 (or 68555 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20151642 is about 4489.0580303667. The cubic root of 20151642 is about 272.1260679300.

Adding to 20151642 its reverse (24615102), we get a palindrome (44766744).

The spelling of 20151642 in words is "twenty million, one hundred fifty-one thousand, six hundred forty-two".