61987988 has 6 divisors (see below), whose sum is σ = 108478986. Its totient is φ = 30993992.

The previous prime is 61987957. The next prime is 61987999. The reversal of 61987988 is 88978916.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 61653904 + 334084 = 7852^2 + 578^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7748495 + ... + 7748502.

It is an arithmetic number, because the mean of its divisors is an integer number (18079831).

Almost surely, 2^61987988 is an apocalyptic number.

It is an amenable number.

61987988 is a deficient number, since it is larger than the sum of its proper divisors (46490998).

61987988 is a wasteful number, since it uses less digits than its factorization.

61987988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15497001 (or 15496999 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 56.

The square root of 61987988 is about 7873.2450743007. The cubic root of 61987988 is about 395.7635989978.

The spelling of 61987988 in words is "sixty-one million, nine hundred eighty-seven thousand, nine hundred eighty-eight".